| 摘要 |
<p>PURPOSE:To realize a high speed shutter with a simple circuit constitution. CONSTITUTION:This exposure controller is provided with a lens optical system 1, an aperture blade 2 being an exposure adjusting mechanism(iris), the actuator 3 of the blade 2, and such an image pickup element 4 as a CCD. Image pickup light from an object is image-formed on the image pickup element 4 by a rear lens optical system 1 whose light quantity is adjusted by the aperture blade 2, and is photoelectrically converted to be outputted to a signal processing circuit 5 as an image pickup signal. A video signal processed at the circuit 5 is recorded on a recording part which is not shown in the figure or outputted to a view finder, etc. A brightness signal Y outputted from the circuit 5 is digitized by an analog/digital converter 6, inputted to a CPU 7, and an aperture controlling signal from the CPU 7 is added through a digital/analog converter 8 on a driver 9 for operating the actuator 3. Hall elements are incorporated in the actuator 3 as a rotation angle detecting means, the output is converted into a digital signal by the analog/digital converter 10, so that the CPU 7 can detect the rotation angle of the actuator 3.</p> |
