Konishiroku Photo Industry Co., Ltd.

Toshiaki Takahashi

Yasushi Hoshino

Masaru Kanbe

Haruhiko Momose

Ken-ichi Kishi

Shinobu Korematsu

Tsuneo Suga

Noboru Itoh

Fumio Shimada

Michio Yagi

Keiji Ogi

Shinichi Nishi

Atsushi Kamitakahara

Kohji Matsushima

Taxey Satoh

Automatic focus adjusting device comprising a range finding means which generates a signal corresponding to a distance to an object to be photographed; means for setting a photographing lens to a position corresponding to the output signal from the range finding means; a primary judging means which judges whether or not a diaphragm setting is within the range in which fixed focus photographing is possible or not; and a secondary judging means which judges whether an output signal from the range finding means is at a level capable of operating an automatic focusing means, wherein the secondary judging means judges only when the primary judging means judges that a diaphragm setting is not within the range in which fixed focus photography is possible and the automatic focusing means is operated only when the secondary judging means judges the output signal is at a level capable of operating the automatic focusing means.

Automatic focus adjusting device

An optical information recording medium for recording and reproducing information by way of applying high density energy beams to a reflective recording layer on a support, said recording layer comprising a hydrophilic colloid; a compound capable of producing a water-insoluble copper complex; and reflective fine particles consisting essentially of copper. A process for manufacturing said optical information recording medium is also provided.

Optical information recording medium

A range finder for measuring the distance of an object to be measured by the steps of radiating the spot light to the object, forming an image of the reflected ray of light by image forming means and measuring the distance of the object from the output of an element which is disposed at a position substantially corresponding to the image forming position and of which output varies in accordance with the light-receiving position on the light-receiving surface. PSD are used as the element. A focussing detector which includes a semiconductor position detection element PSD placed at a position corresponding to the film surface in a camera or the like and detects the focussing state on the basis of the electric output from the semiconductor position detection element PSD. A focussing detector which comprises image forming means for forming the image of an object; a PSD disposed in such an arrangement that the light-receiving surface thereof is eccentric with respect to the optical axis of an optical system including the image forming means and disposed at the back of the image forming means; and an operation circuit detecting the extreme values of the output of the PSD and producing a focussing signal.

Range finder

Disclosed is a method for preparing a light-sensitive cuprous halide emulsion which comprises reducing cupric ions by an ascorbic acid derivative represented by the general formula: ##STR1## wherein R is a hydrogen atom or a hydroxyl group, and n is an integer of 1 to 4, provided that R is a hydroxyl group when n is 1, or its alkali metal salt, in the presence of halogen ions.

Method for preparing a light-sensitive cuprous halide emulsion

An image-forming method wherein a photosensitive material comprising a support having a photosensitive copper (I) halide emulsion that contains silver halide and which has grains of copper (I) halide crystal dispersed in a binder is subjected to imagewise exposure and development with an alkaline solution is disclosed. The imagewise exposure is effected either in a dry or wet state. The alkaline solution contains compounds selected from at least two of the following three groups: (A) a group consisting of .alpha.-amino acids, .alpha.-amino acid derivatives, aliphatic carboxylic acids, oxycarboxylic acids, ketocarboxylic acids, aromatic carboxylic acids, amines, amine derivatives, aminocarboxylic acids, quinoline derivatives and pyridine derivatives, which compounds have a stability constant for Cu(II) complex between 5 and 15; (B) a group consisting of 4-aminophenols and 3-pyrazolidones; and (C) a group consisting of ascorbic acid derivatives of the following formula (I) and alkali metal salts thereof: ##STR1## wherein R is a hydrogen atom or a hydroxyl group; n is a positive integer of from 1 to 4, and when n=1, R represents only a hydroxyl group. The result is an image of improved quality that has a high maximum color density, low fog density, high contrast and a neutral tone.

Method of forming an image with a photographic cuprous halide material

An improved silver halide photosensitive material of the lith-type is disclosed which is suitable for an infectious development in order to obtain high contrast images with high sensitivity. A method for developing the material is also disclosed. The material comprises silver halide grains containing at least 50 mole per cent of silver chloride, less than 40 mole per cent of silver bromide and less than 5 mole percent of silver iodide based on total silver halide, the average size of the grains being 0.05 to 0.5 microns in diameter. The material further comprises a compound represented by the following general formula I or II ##STR1## wherein R is alkyl, aryl, aralkyl or acyl; R' is hydrogen or --OR; and R' is hydrogen or acyl.

Lith-type silver halide photosensitive material containing a

An improved method for adjusting bromide ion concentration in a photographic processing solution is disclosed in which the processing solution is contacted with particles of an insoluble bismuth compound.

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Hino, Japan

Toshiaki Takahashi