Defective pixel detecting circuit of a solid state image pick-up device capable of detecting defective pixels with low power consumption and high precision, and image pick-up device having such detecting circuit

An image pick-up device, comprising:

• image forming means for receiving light from a subject and for forming an image;
• a solid state image pick-up device for converting an optical image formed by said image forming means to an image pick-up signal;
• light intercepting means for intercepting incidence of light to the solid state image pick-up device;
• image memory for storing image pick-up signal of each pixel from said solid state image pick-up device with the light intercepted, as image data;
• and
• defective pixel specifying means for specifying a defective pixel in said solid state image pick-up device, based on the image data in said image memory;
• wherein
• said defective pixel specifying means includes
• operating means for reading image data of one image plane obtained with the light intercepted from said image memory, and for comparing the data with a first threshold value pixel by pixel for extracting a possibly defective pixel, and
• accumulated value calculating means for calculating accumulated value of the image data of each said possibly defective pixel, by reading a prescribed number of times the image pick-up signal from said solid state image pick-up device with the light being intercepted;
• and wherein
• said operating means specifies, by comparing said accumulated value of each said possibly defective pixel with a second threshold value, that possibly defective pixel of which accumulated value exceeds said second threshold value as a defective pixel;
• said image pick-up device further comprising
• interpolating means for interpolating the image pick-up signal corresponding to said defective pixel by using image pick-up signals of surrounding pixels based on data of the defective pixel position specified by said operating means.