Konica Corporation

Konishiroku Photo Industry Co., Ltd.

Makoto Banno

Tatsuji Kurogama

Hiroshi Miyamae

Shigeru Hosoe

Norikazu Arai

Nobuyuki Adachi

Shozo Ishiyama

Kiichirou Ueda

Tadashi Kojima

Nobuyuki Baba

An optical pickup device for recording and/or reproducing information in an optical information recording medium, comprises a light source to emit light flux having a central wavelength not longer than 500 nm; a converging optical system to converge the light flux emitted from the light source onto an information recording surface of the optical information recording medium; and an optical detector to detect light flux reflected from the information recording surface of the optical information recording medium or the light flux passing through the information recording surface of the optical information recording medium; wherein the converging optical system or the optical detector comprises at least one optical element and the optical element comprises at least one optical surface having a center-line mean roughness Ra of 5 nm or less.

Optical element having a low surface roughness, an optical pickup device including the optical element, and a die for making the optical element

The present invention concerns an optical reading apparatus and an optical reading method for obtaining objective information by reading a subject and processing the read information through an arithmetic processing. The optical reading apparatus includes a light source to irradiate a light flux onto a subject; a photo-receiving element to receive a reflected light or a transmitted light of the light flux irradiated onto the subject, and to generate signals based on an opt-electronic converting action; an arithmetic processing section to apply an arithmetic processing to the signals, in order to detect information of the subject; and a calculating section to apply a calculating processing, for reducing noise components caused by optical factors, to the signals generated by the photo-receiving element, in order to obtain output signals in which noise components are reduced, before the arithmetic processing section applies the arithmetic processing to the signals.

Optical reading apparatus and optical reading method

A surface displacement detecting apparatus for detecting a concave, a hole on a surface of a detection object, comprises a light shielding device provided in a direction crossing the surface of the detection object, a light irradiating device provided at one side of the light shielding device and to irradiate the detection object with light; a light receiving device provided at the other side of the light shielding device and to receive at least one of regular reflection light and diffuse reflection light from the surface of the detection object; and a conveyor to convey at least one of the detection object and the light irradiating device.

Displacement measurement apparatus

In a zoom lens apparatus having a lens component which is movable for variation of image magnification, a lens component to compensate for the shift of focus caused by the variation of the image magnification and which is movable to bring an object to be photographed into focus, and a device for driving and positioning each of the lens components, there is provided a controller to control the device. The controller has a position table for each of the lens components and a memory to store the actual positions of the lens components. The controller compares each of the actual positions of the lens components stored in the memory with the position table, based on a signal for a desired magnification so that the zoom lens can focus on a predetermined image plane.

Zoom lens apparatus

When a zoom lens system is focused by moving a lens other than the foremost lens group, the advancing amount of the focusing lens varies according to the variation in the focal length even whyen focusing on an object at the same object distance. When a zoom lens system is zoomed to a certain focal length, the object distance and advancing amount of the focusing lens has a relationship expressed by a function resembling a logarithmic function. The present invention enables one to focus a zoom lens system using only one movement amount curve by arranging to move the focusing lens along the movement amount curve, utilizing different portions of the movement amount curve according to the amount of zooming.

Focusing means for a zoom lens group

As a projection optical system for a measuring projector, a telecentric optical system is required, and, moreover, it is advantageous when a zoom lens system is utilized. The present invention provides a telecentric zoom lens system to be used with a measuring projector wherein an iris is arranged between the lens groups to be moved for variation of magnification and wherein the iris is also moved at the time of zooming in order to prevent increase in the diameter of the front lens and increase in distortion which are caused when the telecentric character is given to a known zoom lens system. To arrange the iris between a second and third lens groups in a zoom lens system comprising four lens groups respectively having positive, negative, positive and positive powers and to enable to move the iris integrally with the third positive lens group, it is preferable to add a negative lens group between the two positive lens groups, i.e., the third and fourth lens groups, so that the zoom lens system comprises five lens groups respectively having positive, negative, positive, negative and positive powers, and to move the added fourth lens group so that it becomes telecentric in respect to the iris, which is fixed to and at the front of the third lens group.

Growing community of inventors

Hachioji, Japan

Makoto Banno