MICROWAVE SAMPLE HOLDER FITTED WITH TRANSISTOR

PURPOSE: To attain optical control of a device by installing an FET provided with an optical controlling device in the channel region between the input of electric signals and the storage capacitor. CONSTITUTION: An FET 6 with an optical controlling device in the channel region between the input 1 of electric signals and the storage capacitor 3 is provided. And when the switching of the transistor 6 is conductive for a very short period, the analog signal existing in the input 1 is stored in the capacitor 3. The input interface processes the sample stored in the capacitor 3 to send to the output 5. Switching of the transistor 6 is controlled by the light coming from a semiconductor laser 9. By this, a sample-hold circuit which is superior in the linearity of response and fast in sampling speed can be obtained.