JPH04344440A - Lens meter - Google Patents

Abstract

PURPOSE:To automatically discriminate whether an inspected lens is a spectacle lens or a contact lens by receiving a reflected light by a light receiving member by way of reflecting a beam projected from a projecting member on the surface of the spectacle lens. CONSTITUTION:A light projecting member 2 consisting of a light emitting diode and others is provided in the neighbourhood of a lens receiving member 1, and a light receiving member 3 consisting of a phototransistor and others is arranged adjacent to it. In the case when an inspected lens is a spectacle lens G, when it is placed on the lens receiving member 1, a beam projected from the light projecting member 2 is reflected on the surface of the spectacle lens G, and its reflected light is received by the light receiving member 3. Subsequently, in the case when the inspected lens is a contact lens CL, as its diameter is small, the projected lighting beam from the light projecting member 2 does not hit on the contact lens CL. Consequently, the reflected light enter the light receiving member 3.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens meter for measuring the apex refractive power of spectacle lenses, contact lenses, etc.

0002

[Prior Art] In recent years, automatic lens meters that automatically measure the apex refractive power of a lens under test and display and print out the measurement results as digital numbers have become popular. The lens meter has a measurement mode for measuring eyeglass lenses and a measurement mode for measuring contact lenses.Switching between these measurement modes is done by manually operating a separate switch. ing.

That is, when switching from the eyeglass lens measurement mode to the contact lens measurement mode, the measurement light beam system becomes smaller, the display contents of alignment marks and measurement values change, and the printout format changes.

0004

[Problems to be Solved by the Invention] However, conventional lensmeters do not have a means to identify whether the lens being tested is a spectacle lens or a contact lens. When measuring, the measurement mode must be changed by manually operating the aforementioned changeover switch.

An object of the present invention is to provide a lens meter that can eliminate the above-mentioned troubles and automatically identify whether a lens is a spectacle lens or a contact lens.

[0006]

[Means for Solving the Problems] A lensmeter according to the present invention for achieving the above-mentioned object is a lensmeter for measuring the refractive power of a test lens consisting of a spectacle lens or a contact lens. Providing a detection means for detecting at least one of the outer diameter, the radius of curvature of the surface, the weight, the presence or absence of a frame, and the presence or absence of a lens holder while in contact with the lens receiving member,
The present invention is characterized by having an identification means for identifying whether the lens to be tested is a spectacle lens or a contact lens based on the detection signal of the detection means.

[0007]

[Operation] The lens meter having the above-mentioned structure determines whether the tested lens is a spectacle lens or a contact lens based on the difference in the properties of the tested lens at the stage when the tested lens is brought into contact with the lens receiving member. to identify.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail based on the illustrated embodiments. Figures 1 and 2 use a light reflection type photosensor.
A first embodiment is shown in which whether a lens to be tested is a spectacle lens or a contact lens is identified based on the difference in outer diameter. FIG. 1 shows a state in which a spectacle lens G is placed on the lens receiving member 1 for measurement, and FIG. 2 shows a state in which a contact lens CL is measured. A light projecting member 2 made of a light emitting diode or the like is provided near the lens receiving member 1, and a light receiving member 3 made of a phototransistor or the like is arranged adjacent to the light projecting member 2. As shown in FIG. 1, when the spectacle lens G is placed on the lens receiving member 1, the light beam emitted from the light projecting member 2 is reflected on the surface of the spectacle lens G, and the reflected light is received by the light receiving member 3. be done.

On the other hand, when the test lens is a contact lens CL as shown in FIG.
Since the diameter of L is as small as about 8 mm, the projected illumination light from the light projecting member 2 does not hit the contact lens CL. Therefore, the reflected light of the projection illumination light does not enter the light receiving member 3.

[0010] Providing such a light reflection type detection means,
Depending on whether the light receiving member 3 receives the reflected light from the lens to be tested, it is possible to automatically identify whether the lens to be tested is the spectacle lens G or the contact lens CL. Note that if a well-known reflection type photosensor in which a light emitting element and a light receiving element are integrated is used as a light reflection type photosensor, the structure can be further simplified and the size can be reduced.

Furthermore, when placing the contact lens CL on the lens receiving member 1, even if the light reflected from the finger of the measurement operator who picks up the contact lens CL is received by the light receiving member 3, the light reflected from the finger is Since the amount of reflected light is stronger than the amount of reflected light from the spectacle lens G, there will be no misidentification if a means for electrical discrimination is provided.

[0012] With such a light reflection type detection means,
If it is possible to identify whether the lens to be tested is a spectacle lens G or not, automatic switching between the measurement modes for spectacle lens measurement and contact lens measurement can be easily performed using an electric circuit.

FIG. 3 is a configuration diagram of the second embodiment, and the radius of curvature of the front curve of the spectacle lens G is about 100 mm, but the radius of curvature of the front curve of the contact lens CL is as small as about 8 mm. By means of detecting the difference in the radius of curvature of the front surface curve of the lens, it is possible to automatically identify whether the lens to be tested is a spectacle lens G or a contact lens CL.

That is, a light emitting member 4 made of a light emitting diode or the like that projects a slit light of a predetermined width as shown in FIG. Image sensor 6 such as a line sensor
An imaging means is provided.

In such a configuration, when the contact lens CL is placed on the lens receiving member 1, since the radius of curvature of the surface curve of the contact lens CL is small,
The reflected image of the slit light from the light emitting member 4 due to surface reflection of the contact lens CL becomes smaller. This reflected image is projected onto the image sensor 6 by the imaging lens 5, and is detected by the image sensor 6 as a narrow slit reflected image S, as shown in FIG.

Furthermore, when the spectacle lens G is placed on the lens receiving member 1, since the radius of curvature of the surface curve of the spectacle lens G is large, the slit reflection image S projected onto the image sensor 6 is shown in FIG. It is detected as a wide slit image.

With such a detection means, it is possible to identify whether the lens to be tested is a spectacle lens G or a contact lens CL, depending on whether the width of the slit reflection image S detected by the image pickup device 6 is narrow or wide. can.

FIG. 7 is a block diagram of a third embodiment of a known lens meter in which identification means is incorporated in the lens receiving portion. The lens receiving member 1 is slightly lifted by an elastic member 7 such as a coil spring, and is held so as to descend when a predetermined weight is applied, and a switch 8 detects when the lens receiving member 1 descends. It looks like this.

When a contact lens CL is placed on such a lens receiving member 1 as shown in FIG. 7, since the weight of the contact lens CL is extremely light, the elastic member 7 can be easily attached to the lens receiving member without being distorted. 1 hardly falls.

Next, when a spectacle lens G attached to a normal frame or a single spectacle lens G before being attached to a frame is placed on the lens receiving member 1, the weight of the spectacle lens G is As a result, the elastic member 7 is distorted, and the lens receiving member 1 is lowered to the lower limit position. Then, the contacts of the switch 8 become energized, and it is electrically detected that the spectacle lens G is placed on the lens receiving member 1.

In such identification means, since the contact lens CL and the spectacle lens G have extremely different weights, if the elasticity of the elastic member 7 is set to a predetermined strength, the weight of the lens to be tested can be reduced. By detecting the difference, it is possible to reliably identify the spectacle lens G and the contact lens CL.

FIGS. 9 to 11 show a fourth embodiment. When measuring a spectacle lens G, operations such as moving the frame backing plate member and fixing it with a lens holding member are performed. This method focuses on the fact that these operations are not performed when measuring CL.

FIG. 9 shows a state in which a spectacle lens G attached to a frame F is being measured, FIG. 10 is a plan view thereof, and FIG. 11 shows a state in which a contact lens CL is being measured. With respect to the auto lens meter 9, the frame abutment member 10 is structured to slide in the front and back direction with extremely light frictional force integrally with the front and rear movable guide rod 1. It has been pulled out to the forward limit position shown by the chain line. And the frame support member 10
The forward limit position of is inevitably pushed in when measuring a spectacle lens G, but when measuring a contact lens CL with a small diameter, it does not touch the contact lens CL and does not interfere with the measurement operation. It is said to be a predetermined position. Rack gear 1 is attached to the longitudinal movement guide rod 11.
3 is fixed, and the rack gear 13 meshes with a pinion gear 15 that rotates integrally with the shaft of the potentiometer 14. When the frame support member 10 moves back and forth, the movement is electrically detected by the potentiometer 14. The configuration is such that Reference numeral 16 denotes a lens holding member, which is lowered when measuring the spectacle lens G, and presses and fixes the spectacle lens G placed on the lens receiving member 1 with a predetermined pressure.

When measuring an eyeglass lens G attached to a normal frame using a lens meter having the frame abutment member 10 having such a structure, the steps shown in FIGS. 9 and 10 are used.
As shown in , the frame F is placed on the frame abutment member 10 and while being pushed against the tension spring 12, the measurement part of the eyeglass lens G is aligned in a predetermined positional relationship with respect to the measurement optical axis of the lens meter 9. After performing this, the eyeglass lens G is held down with the lens holding member 8 and the measurement is performed.

On the other hand, when measuring a contact lens CL, as shown in FIG.
Measurements are taken without moving 0.

In the lens meter 9 having such a frame abutting member 10, if the frame abutting member 10 is moved during the measurement operation of the lens to be tested, this is electrically detected by the potentiometer 14. Then, based on the detection signal of the potentiometer 14, it is identified that the lens to be tested is a spectacle lens G. If the frame fitting member 10 is not moved during the measurement operation of the test lens, the test lens is contact lens C.
It is identified as L.

FIG. 12 is a plan view of the fifth embodiment, which detects the movement of the frame abutting member 17 in the left-right direction. The frame support member 17 is L-shaped and has a structure that allows it to slide in the left-right direction with a light force, and is held by a longitudinal movement guide rod 18 and is normally placed at a limit position indicated by a chain double-dashed line by a tension spring 19. is being drawn to.

[0028] This left-right movement restriction position is the position of the spectacle lens G attached to the frame F or the frame F.
When measuring the spectacle lens G before it is attached to the lens receiving member 1, it is necessary to move the spectacle lens G in the left and right direction.
cannot be placed on the

When measuring the contact lens CL, the frame abutment member 17 is placed in a predetermined position so that the contact lens CL does not touch the L-shaped abutment part of the frame abutment member 17 and does not interfere with the measurement operation. Set 17. Further, an encoder scale plate 20 is attached to the frame abutment member 17, and the frame abutment member 1
When 7 moves in the left and right direction, it can be electrically detected by a photo encoder 21.

In the lens meter having the frame abutting member 17 configured as described above, when the spectacle lens G is placed on the lens receiving member 1, the frame abutting member 17 is arranged as shown in FIG.
It is inevitably moved left and right as shown in . When the frame abutting member 17 is moved in the left-right direction, this movement is electrically detected by the photo encoder 21, and the detected lens is identified as the spectacle lens G based on this detection signal.

On the other hand, during the measurement operation, the frame abutting member 17
If there is no movement, the test lens is contact lens CL.
.

FIG. 13 is a side view of the sixth embodiment. By detecting whether or not the lens holding member 22 is lowered during the measurement operation of the test lens, it is possible to determine whether the test lens is a spectacle lens G or a contact lens. This is to identify whether the lens is CL or not. The lens pressing member 16 disposed above the lens receiving member 1 is pulled downward by a spring 23, and has the function of pressing the spectacle lens G with a predetermined pressure. Stop member 24
It is structured to be locked by. Reference numeral 25 denotes a microswitch, which electrically detects whether the lens pressing member 16 is locked at the upper limit position or lowered to hold the lens to be tested.

In this embodiment, when measuring the eyeglass lens G, after the lens G to be tested is placed on the lens receiving member 1, the locking member 24 is released and the lens holding member 22 is lowered. The apex refractive power is measured while the lens G to be tested is held and fixed.

On the other hand, when measuring the contact lens CL, the contact lens CL is simply placed on the lens receiving member 1 without using the lens holding member 16.

Here, during the measurement operation, the lens holding member 1
6 is used, that is, whether the microswitch 23 is switched or not, the test lens is the spectacle lens G.
or contact lens CL.

Therefore, in all the embodiments described above, when switching the measurement mode between the measurement of the eyeglass lens G and the measurement of the contact lens CL, the identified measurement can be performed without bothering to operate the changeover switch as in the conventional case. Modes can be switched automatically.

[0037]

Effects of the Invention As explained above, the lens meter according to the present invention can measure the apex refractive power of a lens to be tested at the stage where the lens to be tested is brought into contact with the lens receiving member while following the operating procedure for measuring the apex refractive power of the lens to be tested with the lens meter. It is possible to reliably identify whether the lens to be tested is a spectacle lens or a contact lens.

[Brief explanation of drawings]

FIG. 1 is a side view of a first embodiment.

FIG. 2 is an explanatory diagram when a contact lens is placed.

FIG. 3 is a side view of the second embodiment.

FIG. 4 is a perspective view of a light emitting member.

FIG. 5 is an explanatory diagram of a reflected image from a contact lens.

FIG. 6 is an explanatory diagram of a reflected image from a spectacle lens.

FIG. 7 is a configuration diagram of a third embodiment.

FIG. 8 is an explanatory diagram when a spectacle lens is placed.

FIG. 9 is a side view of the fourth embodiment.

FIG. 10 is a plan view.

FIG. 11 is an explanatory diagram when a contact lens is placed.

FIG. 12 is a plan view of the fifth embodiment.

FIG. 13 is a side view of the sixth embodiment.

[Explanation of symbols]

1 Lens receiving member 2 Light projecting member 3 Light receiving member 4. Light-emitting member 6 Imaging device 8 Switch 9 Auto lens meter 10, 17 Frame support member 12 Tension spring 14 Potentiometer G Glasses lenses CL contact lenses

Claims (1)

[Claims] 1. In a lens meter that measures the refractive power of a test lens consisting of a spectacle lens or a contact lens, the outer diameter and surface of the test lens are measured while the test lens is in contact with a lens receiving member. A detection means for detecting at least one of the radius of curvature, weight, presence or absence of a frame, and presence or absence of a lens holder is provided, and based on the detection signal of the detection means, it is possible to determine whether the lens to be tested is an eyeglass lens or a contact lens. What is claimed is: 1. A lens meter characterized by having an identification means for identifying whether the lens meter is