Electrically addressable opto-electronic indicator for making dynamic evaluations of microscopic or larger subjects

A computer controlled image forming apparatus for making quantitative evaluations relating to an image of a subject which is programmed to control a plurality of associated electrically addressable indicia the images of which are viewable superimposed upon the image of the subject. The device is usable for measuring distances, areas, angles, curves, and the like, and is controllable by an operator who, by means of first signals input into the computer, selectively addresses particular members of the plurality of indicia by means of second signals output by the computer and conditioned by interface circuitry in a manner to quantitatively relate the addressed indicia to the image of the subject. Subsequently, the computer interprets the finally addressed indicia in terms of a physical parameter exhibited by the image of the subject for which the computer has been programmed and outputs results of the computations, in the form of third signals, or display to the operator. The questions raised in reexamination request No. 90/003,389 filed Apr. 6, 1994, and 90/003,772 filed Mar. 29, 1995, have been considered and the results thereof are reflected in this reissue patent which constitutes the reexamination certificate required by 35 U.S.C. 307 as provided in 37 CFR 1.570(e).