Imaging apparatus

The present invention relates to an imaging device such as a digital camera provided with a foreign matter removing mechanism for removing foreign matter adhering to the surface of an optical member.

In recent years, image pickup devices using image pickup elements such as digital cameras have become widespread, but especially in single-lens reflex type digital cameras, foreign matter adheres to the surface of optical members such as image pickup elements and filters, and photography is performed. There was a problem that an image of a foreign object was reflected in the image. This foreign matter is dust that enters the image pickup aperture from the outside when the lens is replaced, and wear powder that is generated by the operation of mechanical parts such as a quick return mirror and a focal plane shutter.

In some cases, foreign matter can be removed by blowing air on the surface of the optical member, but it is difficult to completely remove the foreign matter. In such a case, it is necessary to wipe the surface of the optical member to remove the foreign matter. It becomes. However, if the surface of the optical member is manually wiped, uneven wiping may occur or the surface of the optical member may be scratched.

Therefore, some devices have been proposed for easily removing foreign matter adhering to the surface of the optical member. A method has been proposed in which the optical member is vibrated to drop foreign matter adhering to the surface, and it is actually being mounted on a camera. However, if vibration is applied more than necessary, problems such as cracking of the vibrating optical member may occur, and there is a limit to the vibration that can be applied. Therefore, there is a problem that foreign matter having a large adhesive force or sticky foreign matter cannot be completely removed by the vibration type foreign matter removing device.

Several other methods have also been proposed for removing foreign matter adhering to the surface of the optical member. Patent Document 1 states that the surface of the image sensor is exposed, a foreign matter adsorbing member is allowed to enter the camera imaging optical path from the outside, and the adsorbing member is brought into contact with the image sensor surface at an appropriate contact pressure to remove the foreign matter. Is disclosed.

Patent Document 2 discloses that a camera incorporates a wiper member that contacts and scans the surface of an image sensor by driving a motor.

Patent Document 3 discloses that a member that scans on the surface of an image sensor in a non-contact state is charged, and foreign matter is removed from the surface of the image sensor by an electrostatic force.

<patcit num="1"><text>Japanese Patent Application Laid-Open No. 2005-292404</text></patcit><patcit num="2"><text>Japanese Unexamined Patent Publication No. 2001-298640</text></patcit><patcit num="3"><text>Japanese Unexamined Patent Publication No. 2006-119461</text></patcit>

<p> The device shown in Patent Document 1 is an accessory device that is operated by being attached to the outside of the camera, and the lens must be removed and the accessory device must be attached when cleaning is required, which complicates the work. There was a problem that the shooting timing was missed.</p><p> The device shown in Patent Document 2 can easily remove foreign matter at an arbitrary timing by incorporating a wiper member or the like inside the camera. However, since the wiper member is arranged between the shutter blade and the image sensor, there are restrictions on the arrangement of parts. In particular, the shutter efficiency is lowered when the shutter blade traveling surface is separated from the image pickup surface, and the moving object can be stopped at high speed for a second. There was a problem that it was inferior.</p><p> Further, if the shutter efficiency is not lowered as much as possible, it is necessary to reduce the thickness of the wiper member or the like, which causes a problem that the strength and the position accuracy are deteriorated. In particular, if the wiper member is limited to a thin material, the spring constant becomes large even for an elastic body, and it becomes difficult to apply a constant pressure to the surface of the image sensor. There is a concern that the pressure may change significantly due to a slight dimensional accuracy error of the wiper member or the like, resulting in a situation in which foreign matter cannot be removed or a flaw may occur.</p><p> In the device shown in Patent Document 3, by using the charged portion as the shutter blade, it is possible to minimize the restrictions on the arrangement of parts and the decrease in shutter efficiency. However, as the moment of inertia of the shutter blades increases, it becomes impossible to achieve high-speed seconds, and there arises a problem that the durability is inferior. Further, if a charging member is separately provided and an attempt is made to scan between the shutter device and the image pickup element, there are restrictions on the arrangement of parts as in Patent Document 2, and the shutter blade traveling surface is separated from the image pickup surface, so that the shutter efficiency is improved. There is a problem that it is reduced and the ability to stop the moving object at high speed is inferior.</p><p> The present invention has been made in view of the above points, and an object of the present invention is to be able to install a foreign matter removing mechanism without deteriorating the shutter performance and the foreign matter removing ability, and to efficiently install the foreign matter removing mechanism. And.</p>

<p> The image pickup apparatus of the present invention includes a foreign matter removing member that removes foreign matter by moving along the surface of the optical member, and a shutter blade that is arranged on the subject side of the optical member to open and shield the photographing optical path. The foreign matter removing member moves independently of the shutter blade, and the moving locus of the foreign matter removing member and the moving locus of the shutter blade are on the same plane perpendicular to the optical axis, and the shutter. The foreign matter removing member moves along the surface of the optical member when the blade opens the photographing optical path.</p>

<p> According to the present invention, the foreign matter removing mechanism can be installed without deteriorating the shutter performance and the foreign matter removing ability, and the foreign matter removing mechanism can be efficiently installed.</p>

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. &lt;First embodiment&gt; FIG. 1A is an exploded perspective view of the internal structure of a digital single-lens reflex camera. Inside the camera body (not shown), from the subject side, a mirror box 10 having a mount for attaching a lens, a focal plane shutter type shutter unit 20, a mainframe 50, and an image sensor unit 100 including a foreign matter removing mechanism are included. Is placed. FIG. 1 (b) is a perspective view showing a state in which these components are assembled.

2 (a) and 2 (b) are perspective views of the states of FIGS. 1 (a) and 1 (b) as viewed from the image sensor side, respectively.

(Image sensor unit 100) The configuration and operation of the image sensor unit 100 will be described with reference to FIGS. 3 and 4. FIG. 3 is an exploded perspective view of the image sensor unit 100. FIG. 4 is a perspective view showing the assembled state of the image sensor unit 100, in which (a) shows a state in which the foreign matter removing member is retracted, and (b) shows a state in which the foreign matter removing member is moved to the lower end of the LPF 104. ..

The image sensor 101 is attached to the back surface side of the base plate 102, and other parts described later are assembled to the front surface side which is the subject side.

A motor angle 109 is arranged on one short side of the image sensor 101 on the surface side of the base plate 102. The motor angle 109 has a shape extending parallel to the short side (side side) of the image sensor 101, and moves the drive motor 110, the lead screw 111 fixed to the rotation output shaft of the drive motor 110, and the foreign matter removing member. A guide bar 112 that guides the motor is assembled.

Further, a guide angle 113 is arranged on the other short side side of the image sensor 101 on the surface side of the base plate 102. That is, the guide angle 113 is arranged so as to face the motor angle 109 with the image sensor 101 in between. The guide angle 113 has a shape extending in parallel with the short side (side side) of the image sensor 101, and the guide bar 114 is assembled.

A low-pass filter (LPF) 104 fitted in the LPF frame 103 is arranged in front of the image sensor 101. LPF104 is an optical member that plays a role of suppressing the occurrence of false color and moire by cutting unnecessary frequency components and the like. After positioning the antireflection masks (image frame masks) 105 to the left and right of the LPF 104, the LPF fixing frame 106 is fixed to the LPF frame 103, and the LPF 104 is fixed.

In this way, the drive unit (motor angle 109, etc.) and the guide unit (guide angle 113, etc.) are arranged with the LPF 104 in between. The drive unit (motor angle 109, etc.) and the guide unit (guide angle 113, etc.) reciprocate the foreign matter removing member (support plate 108 and flocking member 107) to remove the foreign matter adhering to the surface of the LPF 104.

Specifically, one end of the support plate 108 is fixed to the drive guide 115 with a screw so that the drive guide 115 can move along the guide bar 112. The guide bar 112 is fixed to the motor angle 109 after the drive guide 115 is inserted. Further, the drive rack 116 is fixed to the drive guide 115, and the drive rack 116 is connected to the reed screw 111. The drive rack 116 has the same thread pitch as the lead screw 111.

Further, a flat plate portion and an L-shaped bent portion are provided adjacent to each other at the other end of the support plate 108, and engage with the guide bar 114 in the form of sandwiching the guide bar 114.

The rotational force of the drive motor 110 is transmitted from the lead screw 111 to the drive rack 116, and the drive guide 115 moves along the guide bar 112 to reciprocate the foreign matter removing member.

In the foreign matter removing member, a portion recessed in the direction away from the LPF104 side is formed in the central portion of the support plate 108. Here, a bent portion is formed which is bent so that the central portion of the support plate 108 is lowered by one step, and the flocking member 107 is adhesively fixed to the bent portion. Since the support plate 108 is provided with a bent portion to provide the flocking member 107, the flocking paper or brush made of long hair can be adhered and fixed. With this configuration, it is possible to obtain an effect that the contact pressure on the surface of the LPF 104 can be easily adjusted during the foreign matter removing operation. In other words, the elasticity is lowered by lengthening the bristles, the pressure fluctuation is small even with a slight change in the contact state, and even if there is an error in the distance between the flocked member 107 and the surface of the LPF 104 due to the variation in the shape of the parts, the foreign matter removal ability varies. Can be reduced. In addition, since the hair is deformed and comes into contact with the surface of LPF104, the contact area is increased and the foreign matter removing ability is improved. Even if the foreign matter is a sticky substance or liquid, it can be removed. Is also possible.

Since the bent portion is formed on the support plate 108 in this way, the bent portion protrudes toward the shutter unit 20, but it is configured so as not to interfere with the shutter unit 20 as described later.

The support plate 108 is fixed to the drive guide 115 with a screw. By removing this screw and rotating the support plate 108 around the guide bar 114 to stand up, the flocking member 107 can be easily replaced. It can be carried out.

The LPF guide 121 is attached to the upper end surface of the end surface of the LPF 104 in the scanning direction of the foreign matter removing member, and the foreign matter catching portion 122 is attached to the lower end surface.

The LPF guide 121 is provided on the retracted position side of the foreign matter removing member, and prevents the flocking member 107 from being scraped when it comes into contact with the upper end surface of the LPF 104. The LPF guide 121 is fixed on the same surface as the surface of the LPF 104 and is made of a softer material than the flocking member 107 such as resin or rubber. The contact portion with the flocking member 107 is R-shaped to alleviate the contact pressure and friction. ing.

The foreign matter catching unit 122 is an adhesive member for catching foreign matter that has fallen from the flocking member 107 or adhered to the flocking member 107 when the foreign matter removing member moves near the lower end surface of the LPF 104. ..

Further, the rotation removing unit 119 for cleaning the flocking member 107 in the process of moving the foreign matter removing member from the retracted position onto the surface of the LPF 104 is provided. The rotation removing portion 119 is rotatably supported by the LPF fixing frame 106 and has springs 120 on the left and right sides.

When the foreign matter removing operation is started and the foreign matter removing member moves from the retracted position onto the surface of the LPF 104, the flocking member 107 comes into contact with the rotation removing portion 119. It touches the wall of the wall and cannot rotate. Therefore, since the rotation removing portion 119 exists as a fixing member in the process of moving the foreign matter removing member, the foreign matter adhering to the flocking member 107 can be removed above the LPF104.

On the other hand, when the flocking member 107 retracts from the surface of the LPF 104 to the retracted position, the flocking member 107 comes into contact with the rotation removing portion 119, and the rotation removing portion 119 is rotatable in this direction. Therefore, the flocking member 107 rotates the rotation removing portion 119 against the elastic force of the spring 120. That is, the foreign matter removing member moves to the retracted position without removing the foreign matter adhering to the flocking member 107 so much, and prevents the foreign matter from reattaching to the surface of the LPF 104.

By the way, when the flocking member 107 is moved while being in contact with the surface of the LPF 104, if the contact state of the flocking member 107 is not appropriate, there may be a portion where foreign matter is insufficiently removed or excessive pressure is applied to the surface of the LPF 104. There is a problem of putting on. Therefore, the scanning height of the foreign matter removing member with respect to the surface of LPF104 can be adjusted. Specifically, when fixing the motor angle 109 and the guide angle 113, a disc spring 117 is interposed between the motor angle 109 and the guide angle 113. Belleville springs 117a and 117b for adjusting the height and inclination of the motor angle 109 and disc springs 117c and 117d for adjusting the height and inclination of the guide angle 113 are arranged coaxially with the screws for fixing the respective angles. This makes it possible to adjust the tightening amount of each screw so that the contact state with the LPF 104 is constant in the scanning range of the foreign matter removing member.

Two photo interrupters (PI) 118 are adhesively fixed to the back surface of the motor angle 109. By inserting the PI shielding portion 115a provided in the drive guide 115 into the PI 118, it is possible to detect whether or not the foreign matter removing operation is completed.

Next, the foreign matter removing operation will be described with reference to FIG. Before the start of the foreign matter removing operation (FIG. 5 (a)), the foreign matter removing member (support plate 108 and flocking member 107) is in the retracted position. When the foreign matter removing operation is started (FIG. 5 (b)), the foreign matter removing member moves downward from the retracted position, and the flocking member 107 comes into contact with the rotation removing portion 119. In this direction, the rotation of the rotation removing unit 119 is restricted, and the foreign matter adhering to the flocking member 107 is blown off above the LPF 104. When the flocking member 107 passes through the rotation removing portion 119, it not only removes foreign matter from the flocking member 107, but also has the effect of preventing the hair from being deformed.

The foreign matter removing member moves further downward, gradually comes into contact with the LPF guide 121 provided on the upper end surface of the LPF 104, and moves onto the surface of the LPF 104. The flocking member 107 moves while contacting the surface of the LPF 104 to remove foreign matter adhering to the surface of the LPF 104. When the foreign matter removing member reaches the lower end of the LPF 104 (FIG. 5 (c)), the flocking member 107 comes into contact with the foreign matter catching portion 122, and the foreign matter adhering to the flocking member 107 is captured by the foreign matter catching portion 122. Here, since the foreign matter catching portion 122 is an adhesive member, the foreign matter adhering to the flocking member 107 is adsorbed.

After that, by reversing the direction of energizing the motor, the foreign matter removing member moves upward, and the flocking member 107 comes into contact with the rotation removing portion 119 (FIG. 5 (d)). Rotation of the rotation removing portion 119 is allowed in this direction, and the flocking member 107 overcomes the rotation removing portion 119 with a slight contact force while rotating the rotation removing portion 119 and returns to the retracted position.

(Shutter unit 20) The configuration and operation of the shutter unit 20 will be described with reference to FIGS. 6 and 7. FIG. 6 is an exploded perspective view of the shutter unit 20. 7A and 7B are perspective views showing a state in which the shutter unit 20 is assembled. FIG. 7A shows a state in which the shutter unit 20 is viewed from the subject side, and FIG. 7B shows a state in which the shutter unit 20 is viewed from the imaging surface side. The shutter unit 20 is arranged on the subject side (mount side) of the LPF 104 in the shooting optical path.

The shutter unit 20 includes two sets of shutter blades, a front blade group (front curtain) 31 and a rear blade group (rear curtain) 33. The front curtain 31 shields the shooting opening before shooting and evacuates from the shooting optical path by the shooting start signal. The moving direction in which the front curtain 31 retracts from the shooting optical path is downward. The rear curtain 33 is retracted from the shooting optical path before the start of shooting, and travels after a predetermined time from the running of the front curtain by the shooting start signal to shield the shooting opening.

These two sets of curtains 31 and 33 are arranged between the shutter plate 21 and the cover plate 30. The front curtain 31 is arranged on the cover plate 30 side, the rear curtain 33 is arranged on the shutter plate 21 side, and the traveling space is partitioned by the intermediate plate 32 so as not to interfere with each other. A photographing opening (opening for an optical path for photographing) is formed at a substantially central position of each of the shutter plate 21, the intermediate plate 32, and the cover plate 30.

The shutter plate 21 is provided with a shutter drive unit. Specifically, a set of a front drive lever 22 for driving the front curtain 31, a front drive spring 23 as a drive source, a rear drive lever 24 for driving the rear curtain 33, and a rear drive spring 25 as a drive source. It is equipped with a lever 26. The set lever 26 is for rotating the front drive lever 22 and the rear drive lever 24 to charge the drive springs 23 and 25, respectively, and setting the set lever 26 to the state before the start of shooting. Above the shutter drive unit, as a control unit for controlling the shutter drive unit, there are a front curtain electromagnet 27 and a rear curtain electromagnet 28 composed of a yoke and a coil, and a wiring board 29 for energizing the coil. Will be installed.

The cover plate 30 functions as a holding plate that regulates the operating range of the front curtain 31 toward the LPF104, and a continuous opening 30a is formed above the photographing opening. The opening 30a serves as a retracting position for the foreign matter removing member, and the bent portion of the support plate 108 is accommodated when the foreign matter removing member is in the retracting position. Further, as shown in FIG. 7B, on the imaging surface side of the cover plate 30, the photographing opening and the circumference of the opening 30a are defined as a thin-walled portion 30b, and the space formed by the thin-walled portion 30b is a foreign matter removing member. (Excluding the bent part of the support plate 108) moves. Even if the opening 30a is further enlarged upward and the upper part of the cover plate 30 is separated (the upper part of the cover plate 30 is completely opened), the evacuation space of the foreign matter removing member is expanded. Good.

Next, the shutter operation will be described. The front drive lever 22 and the rear drive lever 24 each have an iron piece portion, and the yoke and the iron piece portion are in contact with each other before the start of shooting. When the coil of the electromagnet for the front curtain and the rear curtain is energized by the shooting start signal, the yoke and the iron piece are attracted to each other, and the front curtain 31 and the rear curtain 33 are held in the set state even after the set lever 26 is retracted. To.

When the coil for the front curtain is cut off after the retracting of the reflection mirror (not shown), autofocus control, reset of the image sensor 101, etc. are completed and the image sensor 101 is ready for shooting, the driving force of the leading spring 23 causes the tip. Curtain 31 runs. Then, after a predetermined time, when the coil energization for the rear curtain is cut off, the rear curtain 33 travels due to the driving force of the rear drive spring 25, and the exposure operation is performed. The set lever 26 is set by a charge lever (not shown), and the front curtain 31 and the rear curtain 33 are set to the states before the start of shooting, respectively, and a series of operations is completed.

(Positional relationship between the cover plate 30 and the foreign matter removing member) Here, a comparison is made between the conventional positional relationship between the cover plate and the foreign matter removing member and the positional relationship between the cover plate and the foreign matter removing member in the present embodiment. FIG. 17 is a diagram schematically showing a configuration around a foreign matter removing mechanism according to the prior art. For easy comparison, the components corresponding to the components described in the present embodiment will be described with the same reference numerals. From the subject side, a shutter plate 21, a rear curtain 33, an intermediate plate 32, a front curtain 31, a cover plate 30, a foreign matter removing member (support plate 108 and a flocking member 107), an LPF 104, an image sensor 101, and the like are arranged.

FIG. 17A shows a state in which the foreign matter removing member is retracted, and the foreign matter removing member is retracted to the back surface of the cover plate 30. FIG. 17B shows a state in which the foreign matter removing operation is in progress, and the foreign matter removing member reaches the lower end of the LPF104. In the conventional configuration, since the foreign matter removing member moves in the gap between the cover plate 30 and the LPF 104, the size is limited, and the hair length of the flocking member 107 cannot be sufficiently secured. The short bristles increase the rigidity and may cause scratches on the surface of the LPF104. In addition, it is difficult to achieve the same contact state over the entire scanning area, and foreign matter is likely to be left behind. It is not easy to secure a gap between the cover plate 30 and the LPF 104 by thinning the cover plate 30 or the LPF 104, which may affect the shutter performance and the optical performance.

On the other hand, as shown in FIG. 5, also in this embodiment, the shutter plate 21, the rear curtain 33, the intermediate plate 32, the front curtain 31, the cover plate 30, and the foreign matter removing member (support plate 108 and flocking member 107) are also viewed from the subject side. ), LPF104, image sensor 101, etc. are arranged.

However, as shown in FIG. 5A, with the foreign matter removing member retracted, the bent portion of the support plate 108 of the foreign matter removing member is housed in the opening 30a of the cover plate 30, and a part of the foreign matter removing member is accommodated. It fits within the thickness of the cover plate 30. In the present embodiment, the depth of the bent portion of the support plate 108 is such that it does not protrude beyond the surface of the cover plate 30 on the front curtain 31 side. Moreover, since the retracting position of the foreign matter removing member is above the cover plate 30 and on the side opposite to the retracting direction (downward direction) of the front curtain 31, the foreign matter removing member does not interfere with the operation of the front curtain 31. .. Further, since the rear curtain 33 is arranged closer to the subject than the intermediate plate 32, the foreign matter removing member does not interfere with the operation of the rear curtain 33, and there is no hindrance to the shutter operation. In this configuration, the space for the foreign matter removing member becomes wider than before, and the length of the hair of the flocking member 107 can be increased. At the retracted position of the foreign matter removing member, the flocking member 107 is not in contact with other members, and there is no risk of the hair being deformed.

Further, during the above-mentioned foreign matter removing operation, the shutter is prohibited from operating, and the user is notified by displaying on a display monitor or the like that the foreign matter removing operation is in progress (processing example by the notification means according to the present invention). .. During the foreign matter removal operation, the front curtain 31 of the shutter unit 20 keeps the photographing opening covered to prevent foreign matter from entering from the outside.

FIG. 8 shows an operation sequence when a shooting instruction is given during the foreign matter removal operation (cleaning operation). During the foreign matter removing operation, it is determined whether or not the foreign matter removing operation is completed by the PI signal or the like by the PI 118 and the PI shielding unit 115a (step S101). If the release button is pressed while the foreign matter removal operation is not completed (step S102), the motor energization is switched to the retracting direction (step S103) to forcibly terminate the foreign matter removing operation, and the foreign matter removing member is retracted. Evacuate to the position. After confirming that the foreign matter removing member has retracted (step S104), the shutter is set to a ready-to-shoot state (step S105). At that time, if the voltage to the motor is increased so that the motor can be retracted at a higher speed than usual, it is possible to prevent the shutter chance from being missed.

In the present embodiment, the configuration for removing foreign matter adhering to the surface of the LPF 104 as the optical member according to the present invention has been described, but the foreign matter adhering to the surface (surface of the cover glass) of other filters or the image sensor 101 has been described. May be configured to remove.

Further, there are various types of focal plane shutters other than the shutter configuration of the present embodiment, and the shutter configuration is not limited. In short, the opening 30a may be provided on the side opposite to the retracting direction of the shutter blade traveling on the side close to the LPF 104 so that it can be used as the retracting position of the foreign matter removing member. Therefore, it is not limited to the arrangement and running direction of the front and rear curtains, and it is also applicable to the normally open type shutter that allows the subject image to be displayed on the monitor by opening the shooting opening before the start of shooting. It is possible. Further, it can be applied to a type of shutter that has only one set of shutter blades and controls the exposure by the shutter function of the image sensor itself and shields the shooting aperture to cut unnecessary light when the exposure is completed.

As described above, by locating the cover plate 30 and a part of the foreign matter removing member on the same plane perpendicular to the optical axis X (see FIG. 5), compactness is achieved, and shutter performance and foreign matter removal are achieved. A foreign matter removal mechanism can be installed without reducing the capacity.

&lt;Second embodiment&gt; A second embodiment will be described with reference to FIGS. 9 and 10. Hereinafter, the points different from those of the first embodiment will be mainly described, and the description of the same configuration and operation will be omitted. The second embodiment is different from the first embodiment in the shape of the bent portion of the support plate 108 of the foreign matter removing member and the shape of the flocking member 107, and the foreign matter removing operation and the shutter operation sequence are different.

In the foreign matter removing member, a bent portion is formed in the central portion of the support plate 108 so as to be lowered by one step in the direction away from the LPF104 side, but the depth thereof is deeper than that in the first embodiment. As a result, as shown in FIG. 9, the bent portion of the support plate 108 protrudes beyond the surface of the cover plate 30 on the front curtain 31 side. By deepening the bent portion in this way, the length of the hair of the flocking member 107 can be further lengthened, the contact state with the LPF104 can be adjusted more easily, the foreign matter removal performance can be improved, and the LPF104 has a flaw. It can be prevented.

In the first embodiment, the movement locus of the front curtain 31 and the movement locus of the foreign matter removing member are not on the same plane perpendicular to the optical axis. On the other hand, in the present embodiment, since the bent portion of the support plate 108 protrudes beyond the surface of the cover plate 30 on the front curtain 31 side, the movement locus of the front curtain 31 and the movement locus of the foreign matter removing member are at least one. Overlap in the part. That is, at least a part of the cover plate 30 and the foreign matter removing member is on the same plane perpendicular to the optical axis.

Next, the foreign matter removing operation will be described with reference to FIGS. 9 and 10. When the foreign matter removing operation is started, the front curtain 31 arranged on the imaging surface side is first retracted downward (step S201), and the rear curtain 33 is expanded (step S202) to shield the photographing opening. In addition, a display is performed on the display monitor to notify the user that the foreign matter removal operation is in progress (step S203). A display example at this time is shown in FIG. This display continues until the foreign matter removal operation is completed (step S205).

Next, the foreign matter removing member is moved downward from the retracted position (FIG. 9 (b)) (step S204). The foreign matter removing member moves on the traveling surface of the front curtain 31, but does not interfere with the front curtain 31 because it has already been retracted. The timing at which the foreign matter removing member starts to move from the retracted position does not have to be after the front curtain 31 is completely retracted to the outside of the shooting opening, and may be the same as or slightly delayed from the movement of the front curtain 31. Good.

After the foreign matter adhering to the flocking member 107 is wiped off by the rotation removing unit 119, the flocking member 107 moves while contacting the surface of the LPF 104 to remove the foreign matter adhering to the surface of the LPF 104. When the foreign matter removing member reaches the lower end of the LPF 104 (FIG. 9 (c)), the flocking member 107 comes into contact with the foreign matter catching portion 122, and the foreign matter adhering to the flocking member 107 is captured by the foreign matter catching portion 122.

After that, by reversing the direction of energizing the motor, the foreign matter removing member moves upward, and the flocking member 107 comes into contact with the rotation removing portion 119 (FIG. 9 (d)). Rotation of the rotation removing portion 119 is allowed in this direction, and the flocking member 107 overcomes the rotation removing portion 119 with a slight contact force while rotating the rotation removing portion 119 and returns to the retracted position (step S205).

Subsequently, the front curtain 31 and the rear curtain 33 are set (step S206), and the foreign matter removal operation is completed when the image is ready for shooting (step S207).

As described in the first embodiment, when a shooting instruction is given during the foreign matter removing operation, the shooting standby state can be quickly set by executing the operation sequence shown in FIG.

Further, if the shutter blades and the foreign matter removing member are arranged in the above-mentioned relationship, it is not necessary that the front curtain 31 is on the imaging surface side and the rear curtain 33 is on the subject side. The state shown in FIG. 9A is the state immediately after the shutter operation is completed. The rear curtain covers the shooting aperture on the imaging surface side, and the front curtain is retracted upward on the subject side. In this case, the shutter blades are exposed from the bottom to the top, but there is no problem.

&lt;Third embodiment&gt; A third embodiment will be described with reference to FIGS. 11 and 12. Hereinafter, the points different from the first and second embodiments will be mainly described, and the description of the same configuration and operation will be omitted. The third embodiment is different from the second embodiment in the foreign matter removing operation and the shutter operation sequence.

The foreign matter removing operation will be described with reference to FIGS. 11 and 12. When the foreign matter removing operation is started, the front curtain 31 arranged on the imaging surface side is first retracted downward (step S301), and the photographing opening is opened. Since the subject image is incident on the image sensor 101 by retracting the reflection mirror and the like, the subject image is displayed on the display monitor (step S302). A display is displayed to notify that the foreign matter removal operation is in progress by superimposing it on the subject image (step S303), and the foreign matter removing member is moved downward from the retracted position in this state (Fig. 11 (b)) (step S304). .. The image of the image sensor 101 is displayed on the display monitor even during the foreign matter removing operation, and it can be confirmed that the foreign matter removing member is scanning on the surface of the LPF 104. That is, the subject image, the state of the foreign matter removing member, and the indication that the foreign matter removing operation is in progress are superimposed and displayed. This display continues until the foreign matter removal operation is completed (step S305).

After the foreign matter adhering to the flocking member 107 is wiped off by the rotation removing unit 119, the flocking member 107 moves while contacting the surface of the LPF 104 to remove the foreign matter adhering to the surface of the LPF 104. When the foreign matter removing member reaches the lower end of the LPF 104 (FIG. 11 (c)), the flocking member 107 comes into contact with the foreign matter catching portion 122, and the foreign matter adhering to the flocking member 107 is captured by the foreign matter catching portion 122.

After that, by reversing the direction of energizing the motor, the foreign matter removing member moves upward, and the flocking member 107 comes into contact with the rotation removing portion 119 (FIG. 11 (d)). Rotation of the rotation removing unit 119 is allowed in this direction, and the flocking member 107 overcomes the rotation removing unit 119 with a slight contact force while rotating the rotation removing unit 119 and returns to the retracted position (step S305).

Subsequently, the front curtain 31 is set (step S306), the shooting opening is covered again with the front curtain 31, and when the shooting standby state is reached, the display monitor indicates that the foreign matter removal operation is completed (step S307).

As described in the first embodiment, when a shooting instruction is given during the foreign matter removing operation, the shooting standby state can be quickly set by executing the operation sequence shown in FIG.

In the shutter unit of the type described in the first embodiment, in order to open the shooting opening, it is necessary to keep the coil for the rear curtain energized in order to run only the front curtain and keep the rear curtain in the retracted state. is there. Other shutter mechanisms are known to be able to hold the rear curtain without energization and to directly drive the blades with a motor or the like. By using these shutter units, the shutter during cleaning operation can be used. It is also possible to eliminate the energization.

In addition, when a shutter called a normal open type in which both the front curtain and the rear curtain are retracted outside the shooting opening is used, the state before the start of shooting is the state shown in FIG. 11 (b), and the subject. The image is always incident on the image sensor. In such a case, it goes without saying that when the foreign matter removing member retracts, it is sufficient to display on the display monitor that the foreign matter removing operation is completed without covering the photographing opening with the front curtain.

&lt;Fourth embodiment&gt; A fourth embodiment will be described with reference to FIG. Hereinafter, the points different from those of the first to third embodiments will be mainly described, and the description of the same configuration and operation will be omitted. The fourth embodiment differs from the third embodiment in the configuration of the shutter blades.

As shown in FIG. 13, only one set of shutter blades 44 exists between the shutter plate 21 and the cover plate 30, and the exposure amount is controlled by controlling the charge accumulation time of the image sensor 101 itself. The shutter blade 44 is used to shield unnecessary incident light on the image sensor 101. Alternatively, it can also be applied to a type in which the charge accumulation start timing is controlled by the image sensor 101 and the charge accumulation end timing is controlled by the shutter blade 44.

Even when the cover plate 30 is composed of such a set of shutter blades, an opening 30a is provided in the cover plate 30 so that the foreign matter removing member can be retracted on the side opposite to the retracting direction of the shutter blades, as in the above-described embodiment. Form. With this configuration, as shown in FIG. 13A, the foreign matter removing member does not interfere with the shutter blade 44 even when the shutter blade 44 shields the photographing opening. When starting the foreign matter removing operation, as shown in FIG. 13 (b), the shutter blade 44 is first retracted downward, and then the foreign matter is removed as shown in FIGS. 13 (c) and 13 (d). The member is moved from the retracted position to scan on the surface of the LPF104.

&lt;Fifth embodiment&gt; A fifth embodiment will be described with reference to FIG. Hereinafter, the points different from the first to fourth embodiments will be mainly described, and the description of the same configuration and operation will be omitted. The fifth embodiment differs from the second embodiment in the configuration of the foreign matter removing member.

A charging member 201 is attached to the support plate 108. Further, a charging unit 202 and a static elimination unit 203 are arranged above the LPF 104. FIG. 14A shows a state before the foreign matter removing operation, and a part of the support plate 108 protrudes beyond the surface of the cover plate 30 on the front curtain 31 side.

When the foreign matter removing operation is started, the front curtain 31 is retracted downward and the rear curtain 33 is expanded to shield the shooting opening. Next, the foreign matter removing member is moved downward from the retracted position, and when the foreign matter removing member passes over the charging portion 202, the electric charge is stored in the charging member 201 (FIG. 14 (b)). Then, the charging member 201 moves near the surface of the LPF 104 in a non-contact manner, so that foreign matter adhering to the surface of the LPF 104 is sucked and removed by electrostatic force.

After the foreign matter removing member reaches the lower end of the LPF104 (FIG. 14 (c)), the foreign matter removing member moves upward by reversing the motor energizing direction. When the foreign matter removing member passes over the static elimination unit 203, the electrification is removed from the charging member 201, and the foreign matter adhering to the charging member 201 falls (FIG. 14 (d)). Around the static elimination unit 203, an adhesive portion for catching falling foreign matter is provided. Then, it is charged and the shooting opening is covered with the front curtain 31, and the shooting standby state is set.

&lt;Sixth Embodiment&gt; A sixth embodiment will be described with reference to FIGS. 15 and 16. Hereinafter, the points different from the first to fourth embodiments will be mainly described, and the description of the same configuration and operation will be omitted. The sixth embodiment differs from the second embodiment in the configuration of the foreign matter removing member.

A wiper 301 is attached to the support plate 108 via a leaf spring member 302. Further, a removing portion 303 is arranged above the LPF 104, and an adhesive portion 304 is arranged below the LPF 104. FIG. 15A shows a state before the foreign matter removing operation, and a part of the support plate 108 protrudes beyond the surface of the cover plate 30 on the front curtain 31 side.

When the foreign matter removing operation is started, the front curtain 31 is retracted downward and the rear curtain 33 is expanded to shield the photographing opening. Next, the foreign matter removing member is moved downward from the retracted position, but when the foreign matter removing member passes over the removing portion 303, the foreign matter adhering to the wiper 301 is removed. Then, when the wiper 301 moves on the surface of the LPF 104, the wiper 301 comes into contact with the surface of the LPF 104 while deforming (FIG. 15 (b)). A leaf spring member 302 is interposed between the support plate 108 and the wiper 301 so that the contact state with the surface of the LPF 104 does not change even if the wiper 301 is deformed. The wiper 301 is made of rubber, has higher rigidity than flocked paper, and is less likely to be deformed. Therefore, in order to keep the pressure on the LPF 104 constant, a leaf spring member having a lower elasticity than the wiper 301 is arranged between the support plate 108 and the wiper 301. Even if the distance between the support plate 108 and the LPF 104 changes slightly, the leaf spring member 302 absorbs the wiper 301 and the wiper 301 can be brought into contact with the surface of the LPF 104 at a constant pressure.

When the foreign matter removing member reaches the lower end of the LPF 104 (FIG. 15 (c)), the wiper 301 comes into contact with the adhesive portion 304, and the foreign matter adhering to the wiper 301 is captured by the adhesive portion 304. After that, by reversing the energization of the motor, the foreign matter removing member moves upward. When the foreign matter removing member passes over the removing portion 303, the foreign matter adhering to the wiper 301 is removed (FIG. 15 (d)). Then, the battery is charged and the shooting opening is covered with the front curtain 31, and the shooting standby state is set.

FIG. 16 is a perspective view showing a configuration example of the foreign matter removing member in the present embodiment, (a) shows a disassembled state of the foreign matter removing member, and (b) shows an assembled state. A leaf spring member 302 having a plurality of bent portions is fixed to the bent portion of the support plate 108. The rubber wiper 301 is adhered to the metal plate 310, and both ends of the leaf spring member 302 are fixed to the metal plate 310 with screws so that the leaf spring member 302 can be expanded and contracted.

Although FIG. 16 shows a wiper 301 having a wavy cross section, the shape of the wiper is not limited to that shown in the drawing.

By interposing an elastic member between the support plate 108 and the wiper 301 in this way, the wiping residue is eliminated, the pressure is kept constant, and the pressure fluctuation due to wear and deformation due to temperature, humidity and the number of operations is alleviated. be able to. Even when the flocking member 107 described in the above-described embodiment is used, an elastic member may be interposed between the support plate 108 and the flocking member 107. According to the configuration of the present invention, it is possible to secure a space for interposing an elastic member between the support plate 108 and the wiper 301, and it is possible to improve the foreign matter removing ability as compared with the conventional case.

The foreign matter removing member is not limited to the one of the above-described embodiment, and may or may not come into contact with the surface of the optical member as long as it moves along the surface of the optical member to remove the foreign matter. It may be the one. Since the structure is such that a sufficient distance between the support plate 108 and the surface of the LPF 104 can be secured, the flocking member 107 shown in the first to fourth embodiments can be used as a removing member for removing foreign matter adhering to the surface of the optical member. Other than the charging member 201 that exerts the electric attraction force shown in the fifth embodiment and the wiper 301 shown in the sixth embodiment can be considered. For example, sponge, non-woven fabric, rubber, etc. may be used, and an adhesive roller, a rotating brush, or the like may be used. Further, it may be an air blowing device having an air blowing port. Further, a foreign matter removing member may be formed by combining a plurality of these.

<figref num="1">It is a perspective view which shows the internal structure of a digital single-lens reflex camera.</figref><figref num="2">It is a perspective view which shows the internal structure of a digital single-lens reflex camera.</figref><figref num="3">It is an exploded perspective view of the image sensor unit.</figref><figref num="4">It is a perspective view which shows the state which assembled the image sensor unit.</figref><figref num="5">It is a figure which shows typically the structure around the foreign matter removing mechanism in 1st Embodiment.</figref><figref num="6">It is an exploded perspective view of a shutter unit.</figref><figref num="7">It is a perspective view which shows the state which assembled the shutter unit.</figref><figref num="8">It is a flowchart which shows the operation sequence when a shooting instruction is given during a foreign matter removal operation.</figref><figref num="9">It is a figure which shows typically the structure around the foreign matter removing mechanism in 2nd Embodiment.</figref><figref num="10">It is a flowchart which shows the foreign matter removal operation sequence in 2nd Embodiment.</figref><figref num="11">It is a figure which shows typically the structure around the foreign matter removing mechanism in 3rd Embodiment.</figref><figref num="12">It is a flowchart which shows the foreign matter removal operation sequence in 3rd Embodiment.</figref><figref num="13">It is a figure which shows typically the structure around the foreign matter removing mechanism in 4th Embodiment.</figref><figref num="14">It is a figure which shows typically the structure around the foreign matter removing mechanism in 5th Embodiment.</figref><figref num="15">It is a figure which shows typically the structure around the foreign matter removing mechanism in 6th Embodiment.</figref><figref num="16">It is a perspective view which shows the structural example of the foreign matter removing member in 6th Embodiment.</figref><figref num="17">It is a figure which shows typically the structure around the foreign matter removal mechanism by a prior art.</figref>

Code description

10 mirror box 20 shutter unit 21 Shutter plate 30 cover plate 31 First feather group (first curtain) 32 intermediate plate 33 Rear feather group (rear curtain) 44 Shutter blade 50 mainframe 100 image sensor unit 101 image sensor 102 Base plate 104 LPF (Low Pass Filter) 107 Flocking member 108 Support plate 109 motor angle 110 motor 111 Lead screw 112 Guide bar 113 Guide angle 114 Guide bar 115 drive guide 116 rack 201 Charging member 301 wiper 302 leaf spring