| 摘要 |
PROBLEM TO BE SOLVED: To provide an electronic endoscope capable of inhibiting the occurrence of local halation in automatic dimming, and keeping the luminance level of a reproduced image to a proper value as much as possible. SOLUTION: This electronic endoscope is provided with a scope 10, illuminating means 16, 62 for illuminating the front of the tip, an image pickup sensor 14 provided on the tip side, and a dimming means 20 for controlling the quantity of illuminating light by the illuminating means according to a luminance pixel signal obtained from the sensor. The quantity of light is controlled so that the average luminance value of the luminance pixel signal substantially agrees with a designated luminance reference value by the dimming means. The dimming means includes an effective maximum luminance calculating means for calculating the effective maximum luminance value of the luminance pixel signal, a halation state variable calculating means for calculating the halation state variable according to the luminance pixel signal for evaluating the state of generation of a local halation, and a correcting means for correcting the average luminance value so that the average luminance value approximates the effective maximum luminance value side according to the halation state variable.
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