Experimental data are presented for the photosensor‐substrate structure presently used with the ac liquid‐crystal projection light valve. This structure consists of a thin film (sputter deposited) ofn‐type CdS on which is evaporated a thin film ofp‐type CdTe. In an earlier publication, a model was presented which describes the photosensitivity of this structure in terms of the depletion‐width photocapacity of the charge‐storage diode formed by these two coatings. The experimental data presented here correlate well with this model. Among the data presented are data on light‐valve display, photosensor gray scale, and response time. The response‐time data are of particular interest because they show that the projection‐light‐valve photosensor is capable of operation at near‐TV rates. The agreement of the experimental data with model and extrapolation from the model imply that large improvements in sensitivity and response time are still quite possible.
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