Ricoh Company, Ltd.

Toshitatsu Suzuki

Satoshi Yamane

Yoshio Fukushima

Tamio Murano

Ikue Kawashima

A distance measuring apparatus for automatically measuring a distance from a reference point to a subject of interest, such as a subject to be photographed, is provided. The present apparatus includes a position sensitive detector having a photoelectric surface defined between two extreme points. Thus, when a light pulse emitted from the apparatus is reflected by the subject and impinges upon the photoelectric surrface, there is produced a pair of current signals, which are then processed to obtain a distance signal indicating the distance to be measured. Thus, the present apparatus can provide a highly accurate measurement.

Distance measuring apparatus

A distance measuring apparatus for automatically measuring the distance from a reference point to a subject of interest, such as a subject to be photographed, is provided. The present apparatus includes a position sensitive detector, a differential circuit and a pair of detecting/extracting circuits each connected between the detector and the differential circuit, whereby each of the detecting/extracting circuits includes electronic switches which change the mode of operation of the apparatus.

A camera system in which information is transmitted between a camera body and an accessory in the form of a current signal is provided. A voltage-to-current converter is provided in at least either one of the camera body and accessory and a current-to-voltage converter is provided in at least the other of the camera body and accessory. Thus, analog information can be transmitted between the camera body and the accessory with high accuracy even if they have separate voltage sources different in level.

Current signal controlled camera system

A focusing position detection circuit provided with a pair of light receiving element arrays respectively disposed in front of and behind a predetermined focusing plane of an optical system, capable of determining the position of the optical system by the output signals of the light receiving element arrays, and outputting an analog signal corresponding to the position of the optical system in the defocused range, but in the focused range with a predetermined tolerance, outputting a focused signal at a predetermined level.

Focusing-position-detection circuit

A focusing detection device is disclosed wherein an electric output obtained by sequentially driving a group of photoelectric elements disposed adjacent to one another on an imaging surface is sampled and held for part or the entirety of the output of a photoelectric converter, this held output is nonlinearized to be compared with a preceding held and nonlinearized output of part or the entirety of the output of the photoelectric converter, the compared value is sampled and held, and extreme values of the displacement of the focus of an image rendered to the photoelectric elements from this held output are derived.

Growing community of inventors

Takarazuka, Japan

Toshitatsu Suzuki