JPH05332720A - Method of detecting angle standard of lens mold - Google Patents

Abstract

PURPOSE:To precisely detect the angle standard of a die by using two diffusive reflecting photoelectric sensors in parallel to each other to simultaneously detect two marking-off lines. CONSTITUTION:The emitted lights of diffusive reflecting type photoelectric sensors 21, 22 are contracted by an optical system and converged on the side surface of a die 1. Marking-off lines 11, 12 are drawn in positions having an equal distance from a virtual surface 3 forming an angle standard on the side surface part of the die 1. The distance between the converging points of the two sensors 21, 22 is coincident to the distance between the marking-off lines 11, 12. When the die 1 is rotated around a rotating shaft 4 in the state where the emitted lights of the sensors 21, 22 are converged, the lights of the sensors 21, 22 are transmitted and not detected because of the transparent die 1 in the place where the marking-off lines 11, 12 and a flaw are absent. When passed through the converging point of the sensors 21, 22, the marking-off lines 11, 12 and the flaw 13 are detected because the lights are diffusively reflected on the marking-off lines and the flaw. To determine the angle standard, the position capable of simultaneously detecting the two sensors 21, 22 can be searched.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing process for plastic spectacle lenses.

[0002]

2. Description of the Related Art Plastic spectacle lenses are made by combining two glass molds to create a space and injecting the undiluted solution of the lens into the space to cure them. Astigmatism lenses and multifocal lenses are composed of two molds. The angle of the mold determines the direction of the astigmatic axis and the direction of the progressive focus.

In the conventional angle matching of a lens mold, a marking line attached to an angle reference position on a non-use surface or a side surface portion of the mold is visually discriminated.

[0004]

However, in the conventional method, there is a limit in the accuracy of combination by visual observation, and when an attempt is made to detect a scribe line by a photoelectric sensor or the like, the scribe line and external factors cause the mold to stick to the mold. The scratched mold cannot be used because both scratches cannot be distinguished and both are detected.

[0005]

The lens type angle reference detection method of the present invention is characterized in that two scatter reflection photoelectric sensors are used in parallel to detect two scribe lines at the same time.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for detecting an angle reference of a lens mold according to the present invention will be described with reference to FIG.

FIGS. 1 and 2 are views showing an angle adjusting method of a lens mold according to the present invention. Reference numeral 1 is a mold, reference numerals 21 and 22 are diffuse reflection photoelectric sensors, and reference numerals 11 and 12 are angle reference markings of the mold 1. A line, 13 is a scratch attached to the side surface of the mold due to an external factor, and 5 is a moving table on which the diffuse reflection photoelectric sensors 21 and 22 are mounted.

The mold 1 is made of glass or the like and is transparent.

The light emitted by the diffuse reflection photoelectric sensors 21 and 22 is narrowed down by the optical system, and the focal point is on the side surface of the mold 1.

The scribe lines 11 and 12 are drawn on the side surface of the mold 1 in parallel with each other at positions equidistant from the virtual plane 3 serving as an angle reference.

Two diffuse reflection photoelectric sensors 2 on the mold 1.
The distance between the focal points 1 and 22 is the angle-based marking line 11, 12
Match the distance of.

While the light emitted from the two diffuse reflection photoelectric sensors 21 and 22 is collected on the side surface of the mold, the mold 1 is rotated about the rotation axis 4 passing through the center of the outer diameter of the mold 1. Go
The light emitted from the diffuse reflection photoelectric sensors 21 and 22 is condensed on the side surface of the mold 1 where there is no marking line 11, 12 or scratch 13, but the light is transmitted because the mold 1 is transparent. It will not be detected.

As shown in FIG. 2, when the scribe lines 11 and 12 and the scratch 13 pass through the condensing point of the light emitted from the diffuse reflection photoelectric sensors 21 and 22, the light is diffused and reflected on the scribe line and scratches and is detected. ..

In order to obtain the angle reference, it is advisable to search for the positions detected by the two diffuse reflection photoelectric sensors 21 and 22 at the same time, as shown in FIG.

If the scratch 13 is attached at a position equal to the distance between the scribe lines 11, 12 and the scribe lines 11 and 12, or if the scratch 13 is attached so as to be equal to the distance between the scribe lines 11 and 12, the angle is increased. Although the reference is erroneously obtained, the number of molds that cannot be used can be reduced as compared with the conventional case because such a specific position is rarely scratched.

When there is a mold having a different outer diameter from the mold 1,
When the two diffuse reflection photoelectric sensors 21 and 22 are placed on one moving table 5 and moved in the radial direction 6 of the mold, the mold is arranged so that the outer diameter center of the mold coincides with the rotation axis 4. There is a table position such that the light condensing points of the two diffuse reflection photoelectric sensors 21 and 22 are on the side surface of the mold at the same time, and it is possible to search the angle reference even with the molds having different outer diameters with one detection device. it can.

Although a scribed line is raised as a detection mark here, any two patterns that can be detected by a detector can be used.

This method can be applied not only to the mold but also to the spectacle lens itself.

[0019]

When the above method is used, it is possible to perform automatic combination with higher accuracy than visual combination.

[Brief description of drawings]

FIG. 1 is a diagram showing a method for adjusting an angle of a lens mold according to an embodiment of the present invention.

FIG. 2 is a diagram showing a method for adjusting an angle of a lens mold according to an embodiment of the present invention, showing a state where two diffuse reflection photoelectric sensors detect a scribe line.

[Explanation of symbols]

 1 Type 3 Virtual surface that serves as an angle reference 4 Rotation axis of the mold 1 passing through the center of the outer diameter 5 Moving table 6 Moving direction of the moving table 5

Claims (1)

[Claims] 1. A method for detecting an angle reference of a lens mold, wherein two diffuse reflection photoelectric sensors are used in parallel to detect two scribe lines provided on the side surfaces of the two lens molds at the same time.