A cathode that emits electrons when illuminated, causing an electric current.
- ‘Reflections from the target were focused on a converter unit containing a photocathode, which provided the viewer with a reconstructed image.’
- ‘The quantum efficiency of the photocathode decreases significantly at 830 nm creating an effective acceptance bandwidth of 650-830 nm in fluorescence detection.’
- ‘The photocathode in the night scope that converts visible light into electrons is sensitive to both visible light and some infrared radiation.’
- ‘If excitation light rejection at the photocathode were not an issue, this might simply require an increased integration time or gain setting to acquire a sufficient fluorescence signal for processing.’
- ‘The long-pass and band-pass filter combination was used in these studies at each target depth, and the integration time was varied between 200 and 700 ms because the amount of light collected at the image intensifier photocathode varied.’