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8.5.7 What is auto-iris and how does it work ?
The auto-iris option consists of a servo loop that is made up of the analog video processor and
an auto-iris lens. Circuitry within the auto-iris lens examines the video signal from the video
processor and compares its amplitude to a preset amplitude. If the video amplitude from the
processor is less than the preset level, the iris of the lens is opened wider; if it is more than the
preset, the iris is closed down.
This feedback action keeps the level of the video at the preset value over a range of scene
illumination. Once the auto-iris lens is wide open, decreasing the scene illumination has no
further effect on the auto-iris lens. Typically, the AGC Circuit takes over at this point ! The two
circuits work in tandem to increase the effective dynamic range of the camera.
8.5.8 What is GAMMA - it sounds like Greek to me ?
8.5.9 What options are available to control the Digital Video gain and offset ?
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Страница 14: ...9 Figure 4 3 TC 245 Gate Level Drawing Texas Instruments 1994 ...
Страница 61: ...56 12 Appendix D Camera Mechanical Drawings Figure 12 1 Camera Mechanical Drawings ...
Страница 63: ...58 Figure 13 2 Camera Noise Spectrum Min Gain Bandwidth 10kHz to 4 2MHz ...
Страница 64: ...59 Figure 13 3 Camera Noise Spectrum Max Gain Bandwidth 100kHz to 4 2Mhz ...
Страница 65: ...60 Figure 13 4 Camera Noise Spectrum Max Gain Bandwidth 10kHz to full ...