摘要 |
To measure the spatial response characteristics of optical systems, control circuitry is provided to electrically generate a predetermined one-dimensional spatial waveform (e.g., sinusoidal) on the display screen of a cathode ray tube. The optical system to be tested (e.g., a television system) is placed between the spatial waveform display and a suitable detector which comprises a mask having a narrow slit followed by a photomultiplier. The output of the latter is then displayed on an oscilloscope, or measured in some other known fashion. A linear light modulation is achieved for the spatial waveform display by gating a linearly scanned electron beam with constant amplitude, constant duration, variable duty cycle pulses. Appropriate waveforms can be selected to evaluate the spatial frequency response, transient response, linearity, or steady state response of the optical system under test.
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