Detecting the maximum/minimum diaphragm adjustment value of a lens

摘要

A detector for detecting the maximum/minimum diaphragm adjustment value of an exchange lens of a camera includes a bar code, in which the maximum/minimum diaphragm adjustment value of an exchange lens is printed in a binary code, formed on the lens and a bar code reader on the camera for reading and decoding the bar code. The bar code reader outputs an electric pulse signal corresponding to the bar code by radiating a fixed scanning line at the bar code.