Signal processing circuit for electronic endoscope

TL;DR: In this article, a variable gain amplifier (multiplier) 11 for raising a gain to the object of low illuminance and amplifying, a movement detector 12 for detecting the scale in the change of the time of a picture and the cyclic type noise removing filter 13 for variably controlling the characteristic of the filter according to the output of this movement detector.

Abstract: PURPOSE:To apply for an animation picture and to obtain a picture good in S/N to a low illuminance by disposing the detecting means of the change in time of an image pickup signal and variably controlling the characteristic of a cyclic type noise removing filter. CONSTITUTION:A variable gain amplifier (multiplier) 11 for raising a gain to the object of the low illuminance and amplifying, a movement detector 12 for detecting the scale in the change of the time of a picture and the cyclic type noise removing filter 13 for variably controlling the characteristic of the filter according to the output of this movement detector 12 are provided. Namely, the noise removing filter capable of detecting the change in the time of the picture by the movement detector 12, deciding the coefficient of the filter 13 from this value and the gain setting value of a prestep amplifier 11 and being adapted to the brightness of the object and the movement thereof is constituted. Thereby, the deterioration of the picture to the animation picture is reduced and the picture good in the S/N to the object to the low illuminance can be obtained.