to the terminal in1 of the microprocessor mp through the amplifier g the microprocessor mp supplies a signal which causes the image sensor chip 3 to start the storage to the terminal clr of the image sensor chip 3 the microprocessor mp as well supplying the clock clk1 to the transfer gates 111 112 and 113 the microprocessor mp supplies a signal which causes the image sensor chip 3 to end the storage to the terminal trr of the first control portion while the microprocessor mp receives data for the image sensor array supplied from the second control portion 5 through the terminal in1 so as to a d convert it by an a d converter included therein the microprocessor mp stores the data thus a d converted in a memory thereof as an alternative to the structure arranged as described above in such a manner that the a d converter is included in the microprocessor mp the a d converter may be mounted on the surface of the microprocessor mp however it is not preferable to employ that structure since a camera must have a reduced size the calculations for detecting the focal point are performed by using data columns stored in the memory since the method of calculating the focal.