Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for measuring decentralization of optical axis on the front and the rear surface of lens

A measurement method and technology of eccentricity, applied in the direction of optical axis determination, lens, optical instrument testing, etc., can solve the problems that cannot be processed and corrected, the accuracy cannot meet the requirements, and the shape error cannot be quantitatively evaluated.

Inactive Publication Date: 2008-07-30
MITAKA KOHKI
View PDF2 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] However, this method using the existing automatic collimator cannot quantitatively evaluate the shape error, so that the correction model cannot be processed from the obtained results.
In addition, with the recent trend towards miniaturization and higher NA of aspheric lenses, the allowable value of eccentricity is also required to be below a few microns, and the method using an autocollimator cannot meet the requirements only for accuracy.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for measuring decentralization of optical axis on the front and the rear surface of lens
  • Method for measuring decentralization of optical axis on the front and the rear surface of lens
  • Method for measuring decentralization of optical axis on the front and the rear surface of lens

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] 1 to 7 are diagrams showing an embodiment of the present invention. FIG. 1 is a diagram showing the configuration of a laser probe type shape measuring instrument according to the present embodiment. In FIG. 1 , X and Y represent two directions perpendicular to each other on a horizontal plane, and Z represents a vertical direction. In addition, FIG. 1 is a schematic diagram.

[0024]

[0025] The aspherical lens 1 to be measured has a front surface (first surface) 1a and a back surface (second surface) 1b, and is formed in an aspherical shape. The aspheric lens 1 is supported by a lens holder 2 having a certain thickness and formed of a metal having a low thermal expansion rate. The lens holder 2 is further positioned by a reference pin 21 fixed to a jig of a scanner or the like. A holding hole 3 is formed at the center of the lens holder 2 . The holding hole 3 is formed with a recess 4 corresponding to the diameter of the aspheric lens 1 , and is fixed by a ring...

no. 2 example

[0050] In the optical axis eccentricity measurement device according to the second embodiment of the present invention, since the shape measuring device using the laser probe method and its operation are the same as those of the first embodiment, description of the same parts will be omitted.

[0051] As shown in FIG. 9 , the lens holder 22 of this embodiment has four common reference points, and the reference points 6b, 6d are arranged orthogonally to the arrangement direction of the two reference points 6a, 6c.

[0052] The x-axis passing through these two points is specified by the three-dimensional position measurement of the reference points 6b, 6d, the y-axis passing through these two points and orthogonal to the x-axis is specified by the three-dimensional position measurement of the reference points 6a, 6c, and the z-axis, so that the position is described by the orthogonal coordinate system (x, y, z). A virtual plane defined by the x-axis and the y-axis is the common ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
Lengthaaaaaaaaaa
Login to View More

Abstract

A laser probe is used to measure a cross sectional shape in a first and a second direction at each of apexes at the front and the rear surface of an aspheric lens. The measured cross sectional shape of the front and the rear surface of the aspheric lens is described in a common coordinate system decided according to the 3D position of the measured pin hole (common reference point). According to the measured cross sectional shape, each of the apexes is detected so as to obtain the relative decentralization amount of the front and the rear surface of the aspheric lens with accuracy in the order of micrometers or below.

Description

technical field [0001] The invention particularly relates to a method for measuring the optical axis eccentricity of the front and back surfaces of an aspheric lens. Background technique [0002] Most aspheric lenses are mass-produced by molding techniques using molds. A lens whose two surfaces are composed of a sphere-plane or a sphere-sphere has a shape that is rotationally symmetric to the normal vector at any point on any surface, and there is an axis of rotational symmetry around it on any surface, and the axis is optical axis. However, due to the uniqueness of the axis of rotational symmetry in an aspheric lens, in the case of an aspheric-aspherical or spherical-aspheric lens, it is necessary to process the rotational symmetry axes of both surfaces to coincide during molding. Therefore, in order to improve the machining accuracy, quantitative measurement of the decentering of the aspheric lens becomes an essential operation. [0003] The eccentricity of the optical ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G01B11/24G01B11/00G01M11/00
CPCG01B11/24G01M11/0221G01M11/025G02B3/02G02B19/0052
Inventor 中村胜重三浦胜弘
Owner MITAKA KOHKI