JP4222680B2 - Lens meter - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a lens meter that measures optical characteristics such as refractive power in an optical system.
[0002]
[Prior art]
Conventionally, as described in Japanese Patent Application Laid-Open Nos. 61-280544 and 5-231985, a test lens is placed on a lens base, and a measurement light beam transmitted through the test lens is transmitted. A lens meter is known in which optical characteristics such as spherical power, cylindrical power, and axial angle of a lens to be measured are measured by detection using a photoelectric change type light receiving means.
[0003]
In recent years, various progressive lenses have been sold. However, when these progressive focus lenses are processed into a frame, the positions of the distance portion, the progressive portion, and the near portion are difficult to understand, and in particular, the positions of the distance portion and the near portion are determined subjectively by the measurer. Therefore, there is a problem that skill is required for the measurement, an error is caused in the measurement, and the measurement efficiency is lowered.
[0004]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide a lens meter that can easily measure a progressive focus lens without depending on the level of skill of a measurer.
[0005]
[Means for Solving the Problems]
In order to solve such problems, a feature of the present invention is that the measurement light beam projected from the light emitting means and transmitted through the test lens placed on the lens receiver is a photoelectric conversion type light receiving device. detected by means Oite based on detected value in Renzume data to measure the optical characteristics of the test lens, a mode switching means for switching the progressive lens measuring mode, the measuring means for measuring the optical characteristics of the subject lens directing the storage means for storing the results obtained by the measuring means, based on the results obtained by the measuring means, the progressive portion of the lens under test on the optical axis of the measuring beam in said measuring means a first inductive means, second inductive means for guiding the distance portion of the lens under test on the optical axis of the measuring beam in said measuring means, said test lens on the optical axis of the measuring beam in said measuring means near portion of A third guide means for guiding the deformation square the measuring light beam is formed by being allowed refracted according to the refractive properties of該被subject lens after passing through the four points located at each corner of the rectangle on the subject lens Of these sides, the length of the side located on the distance portion side: Lx1 and the length of the side located on the side of the near portion: Lx2, the difference value: Lx1-Lx2 is set as the progressive amount: P, Using the value of the progressive amount: P obtained from the detection result of the measurement light beam by the light receiving means, and the value of the progressive amount: P obtained by the progressive amount computing means, a measurement point is obtained. Is provided with a position discriminating means for measuring points for discriminating which of the progressive part, the distance part and the near part belongs to.
[0006]
Further, Renzume data according to claim 7, the first inductive means definitive in Renzume data of claim 1, instead of the induction of the optical center, in which to obtain a similar effect.
[0007]
[Action]
The lens meter according to claim 1 detects a measurement light beam transmitted through a test lens placed on a lens receiver by a photoelectric conversion type light receiving means, and determines an optical characteristic of the test lens based on the detected value. Based on the measurement results, it is possible to guide to the progressive part that is the first guiding means, to the distance part that is the second guiding means, and to the near part that is the third guiding means. The three-stage guidance means can easily measure the distance portion and the near portion.
[0008]
Lens meter according to claim 7 is replaced with first inductive means definitive in Renzume data of claim 1 for the induction of the optical center, as well as the three-step test lenses placed in the lens受上by the induction means The distance part and the near part can be easily measured.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.
[0010]
First, FIG. 1 shows a schematic configuration of a measurement optical system as one embodiment of the present invention. In such a measurement optical system, a measurement light beam 12 is emitted from a light source 10 and is condensed and projected in approximately one direction. A collimating lens 16 as a projection optical system is disposed coaxially with respect to the optical axis 14 of the measuring light beam 12 at the projection destination of the measuring light beam 12 by the light source 10 and transmits through the collimating lens 16. Thus, the measurement light beam 12 is made to be a substantially parallel light beam. Further, a lens 18 to be tested is supported by the lens receiver 5 at the tip of the collimator lens 16 and can be arranged substantially coaxially with the optical axis 14 of the measurement light beam 12. The measurement light beam 12 is made to be a substantially parallel light beam and then transmitted to the lens 18 to be measured. Further, a condensing lens 20 and an imaging lens 22 are arranged on the optical axis of the measurement light beam 12 that has passed through the lens 18 to be measured, and are further spaced apart from each other. A light receiving element 24 is disposed apart from the imaging lens 22 on the optical path of the light beam 12. Then, the measurement light beam 12 that has passed through the test lens 18 is condensed by the condenser lens 20 and then guided to the light receiving element 24 by the imaging lens 22. Further, the light receiving surface of the light receiving element 24 is conjugated with the test lens 18 by the condenser lens 20 and the imaging lens 22, and the measurement light incident on a fixed position of the test lens is detected by the test lens. Regardless of the refractive power of 18 or the like, the light is guided to a certain position on the light receiving surface of the light receiving element 24.
[0011]
In short, in the measurement optical system of this embodiment, so as to be positioned pairs toward the optical axis direction both sides across the target lens 18, the light source 10 and the light receiving element 24 is disposed, emitted by the light source 10 The measured measurement light beam 12 is projected onto the test lens 18 through the collimator lens 16, and after passing through the test lens 18, is guided to the light receiving element through the condenser lens 20 and the imaging lens 22, and is supplied to the photoelectric conversion element 26a. It is detected as an electrical signal by ~ d (light receiving point).
[0012]
In the present embodiment, as shown in FIG. 2, on the light receiving surface of the light receiving element 24, the photoelectric conversion elements (light receiving points) 26a, 26b, 26c, and 26d are positioned at the four corners of the square, respectively. A total of four photoelectric conversion elements are provided. The light receiving element 24 is arranged so that the center of the square formed by the four photoelectric conversion elements 26a to 26d is positioned on the optical axis 14 of the measurement light beam 12, and the light receiving surface is arranged perpendicular to the optical axis 14. The positions of the photoelectric conversion elements 26a, 26b, 26c, and 26d are light detection points on the light receiving surface.
[0013]
Further, on the optical path of the measurement light beam 12, a rotary plate 32 having a circular flat plate shape as a rotary chopper located between the condenser lens 20 and the imaging lens 22 is arranged in a direction perpendicular to the optical path. It is installed. The rotary plate 32 is rotationally driven by a drive motor 28 about a rotary shaft 30 that is biased parallel to the optical axis 14 of the measurement light beam 12. Further, the rotating plate 32 has an edge portion that can block the measurement light beam 12 in accordance with the rotational movement around the rotation shaft 30, and the measurement light beam 12 and thus the light receiving element by rotation around the rotation shaft 30. The incident light to 24 is interrupted.
[0014]
In particular, in the present embodiment, as shown in FIG. 3, the substantially fan-shaped window portions 34 are 90 ° apart from each other in the circumferential direction at positions intersecting the optical path with respect to the disk-shaped rotating plate 32. It is formed apart. Further, both edge portions 36 and 38 in the circumferential direction of the window portion 34 have mathematically known shapes. In particular, in the present embodiment, any of the edge portions 36 and 38 is light of the measurement light beam 12. The intersection angles α and β with respect to one circumference 40 as the locus of the intersection with the axis 14 are designed to be 45 °. Furthermore, slits 42 a and 42 b for providing a reference position in the circumferential direction of the edge portions 36 and 38 are formed on the outer peripheral portion of the rotating plate 32. In the present embodiment, the rotating plate 32 is disposed on the light receiving element 24 side from the condenser lens 20 at a position separated by the focal length of the condenser lens 20.
[0015]
In the lens meter having such a structure, when the test lens is disposed on the optical path, each point corresponding to each of the light receiving points 26a to 26d of the light receiving element 24 that is conjugate with the test lens 18 is provided. The light that has passed through is refracted according to the refractive power characteristics (optical characteristics such as spherical power and cylindrical power) of the lens 18 to be measured, so that the position of the rotating plate 32 on the mounting surface is displaced. It becomes. Therefore, by measuring the displacement amount and the displacement direction of the light transmitted through each point of the test lens 18 on the arrangement surface of the rotating plate 32, the optical characteristics of the test lens 18 are determined from these values. It can be sought. The displacement amount and displacement direction of the transmitted light on the arrangement surface of the rotating plate 32 are determined by using the intermittent position by the edge portions 36 and 38 of the rotating plate 32 as the displacement amount of the rotation angle from the reference position. Since it can be known by detecting each of the 24 photoelectric conversion elements 26a to 26d, it can be obtained by the output signal of the photoelectric conversion elements 26a to 26d and the reference position sensor 44 such as a photoelectric switch using the slits 42a and 42b. The reference position signal of the rotating plate 32 is input to an arithmetic processing unit 46 constituted by a microcomputer or the like, and is subjected to arithmetic processing according to a preset program, whereby the target lens 18 has a spherical power and a cylindrical power. Such optical characteristics can be obtained. Note that a calculation method for obtaining optical characteristics such as spherical power and cylindrical power of the test lens 18 based on the output signals of the photoelectric conversion elements 26a to 26d is described in JP-A-5-231985. , Avoid detailed description here.
[0016]
Here, as described above, the position of the test lens 18 and the light receiving element 24 are in a conjugate positional relationship, and the photoelectric conversion elements 26a to 26d of the light receiving element 24 are arranged at the four corners of a square. In the lens 18 to be tested, each point corresponding to each detection point 26a to 26d of the light receiving element 24 which is conjugate forms a square. Then, after passing through the test lens 18, each point is refracted according to the refraction characteristics of the test lens 18, so that the refraction characteristics of the test lens on the arrangement surface of the rotating plate 32. It can be transformed into a square according to
[0017]
Here, when the test lens is a single focus lens, the quadrangular shape formed on the arrangement surface of the rotating plate 32 is a parallelogram, and the lengths of opposite sides are equal. If it demonstrates in FIG. 4, if each edge | side of this square will be Lx1, Lx2, Ly1, and Ly2, respectively,
Lx1 = Lx2 and Ly1 = 1y2 are established.
[0018]
That is, if the progressive amount P is a value calculated from the difference between Lx1 and Lx2,
P = Lx1-Lx2 = 0, and the progressive amount P is 0 (or a certain amount or less).
[0019]
By the way, the progressive focus lens is a lens having three regions of a distance portion, a progressive portion, and a near portion, and the distance portion and the near portion have almost the same optical characteristics as the single focus lens. Therefore, when there is a distance portion or a near portion of the lens to be examined on the lens receiver 5, the quadrangular shape formed on the arrangement surface of the rotating plate 32 is the same as in the case of the single focus lens. It becomes a parallelogram, and the progressive amount P is 0 (or a value equal to or less than a certain amount) as described above.
[0020]
However, when there is a progressive portion of the lens to be tested on the lens receiver 5, the quadrangle formed on the arrangement of the rotating plate 32 is deviated from the parallelogram, and the lengths of the opposite sides are not equal. If it demonstrates in FIG. 5, if each edge | side of this square is set to Lx1 ', Lx2', Ly1 ', Ly2', respectively,
Lx1 ′ ≠ Lx2 ′ and Ly1 ′ ≠ Ly2 ′.
[0021]
That is, P = Lx1-Lx2 ≠ 0, and the progressive amount P has a certain level or more.
[0022]
That is, by calculating the progressive amount P as described above, it is possible to distinguish the progressive portion from the distance portion and the near portion.
[0023]
First, the first guiding means for guiding the progressive lens to the progressive portion will be described.
[0024]
Press the mode switch to enter the progressive focus lens measurement mode. On the screen of the display 1, as shown in FIG. 6A, a target display simulating a progressive focus lens and an alignment coordinate 60 are displayed at the center. The horizontal direction of the coordinate 60 represents the prism amount, and the vertical direction represents the progressive amount. The coordinate 0 in the horizontal direction is set to a prism amount 0, and the vertical 0 position is set to a value greater than a certain fixed value. Here, the certain amount is an amount that can be determined to be a progressive portion. Normally, the amount of prism in the horizontal direction is almost zero, and the amount of progression is more than a certain amount. Therefore, the measurer guides the lens to the progressive portion by aligning the target 61 with the center of the coordinates. Is possible.
[0025]
Next, a description will be given of second guiding means for guiding the progressive focus lens to the distance portion.
[0026]
After guiding the lens to the progressive part, an arrow 62 is displayed on the upper portion of the target display on the screen of the display 1 as shown in FIG. The horizontal and vertical directions of the central coordinate 61 are the prism amount and the progressive amount, respectively, as in the first guiding means. The coordinate 0 in the horizontal direction is set to a prism amount 0, and the vertical 0 position is set to a progressive amount 0 (or a certain amount or less). Here, a certain amount or less is an amount that can be determined to be a distance portion. Usually, in the distance portion, the amount of prism in the horizontal direction is almost 0, and the progressive amount is 0 (or a certain amount or less) as described above, so that the examiner adjusts the target 61 to the center of the coordinates. By moving the lens in the direction of the arrow 62, it can be guided to the distance portion. When the measurer has led the lens to the distance portion, he presses the memory switch 2 to store the refractive power of the distance portion.
[0027]
Next, a description will be given of the third guiding means for guiding the progressive focus lens to the near portion.
[0028]
When the lens is guided to the distance portion and the refractive power of the distance portion is stored, the center coordinates of the alignment display on the screen of the display 1 disappear and the display changes as shown in FIG. The vertical direction of the target 61 represents the addition, and the target 61 moves downward on the screen depending on the magnitude of the addition. Further, the horizontal direction of the target 61 is moved by a value calculated from the difference between the cylindrical refractive power (CYL value) of the distance portion stored at the time of the second guiding means and the cylindrical refractive power at the current measurement position and the prism amount. It has become. Usually, since the calculated value is substantially 0 in the progressive zone, the measurer moves to the near portion while adjusting the lens in the left-right direction so that the horizontal position of the target 61 is in the middle. The shape of the target 61 also changes depending on the progressive amount. When the progressive amount is a certain amount or more (a progressive portion), the shape of the target 61 is “+” and less than a certain amount (the near portion). ), The shape changes to “◯” as shown in FIG. As a result, guidance to the near portion can be performed. When the target 61 changes to “◯”, the measurer presses the memory switch 2 to store the value of the near portion, calculates the addition power (ADD value) of the progressive focus lens, and displays it on the display 1 screen. To do.
[0029]
Further, when the first guiding means is guided to the optical center, the center of the coordinates becomes the optical center, and the measurer can guide the lens to the optical center by aligning the target with the center of the coordinates. The second and third guiding means are the same as those described above.
[0030]
【The invention's effect】
As is apparent from the above description, according to the present invention, it is left to the subjective judgment of the conventional measurer, and the measurement of the distance portion and the near portion that require skill can be measured very easily. As a result, the reliability of the measurement results and the measurement efficiency are increased, and customer serviceability can be improved.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of a measurement optical system as one embodiment of the present invention.
FIG. 2 is a front view of a light receiving element employed in the measurement optical system shown in FIG.
3 is a front view of a rotating plate employed in the measurement optical system shown in FIG.
FIG. 4 is a diagram showing a quadrangular shape (in the case of a distance portion or a near portion) after passing through a test lens.
FIG. 5 is a diagram showing a quadrangular shape (in the case of a progressive portion) after passing through a test lens;
FIG. 6 is a diagram showing an alignment pattern at each guiding stage for a progressive focus lens employed in the present embodiment.
FIG. 7 is an external view of an apparatus according to the present embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Light source 12 Measurement light beam 18 Test lens 24 Light receiving element 26 Photoelectric conversion element (light receiving point)
32 Rotating plate

Claims (7)

The measurement light beam projected from the light emitting means and transmitted through the test lens placed on the lens receiver is detected by the photoelectric conversion type light receiving means, and the optical characteristic of the test lens is measured based on the detected value. In the lens meter,
Mode switching means for switching to the progressive lens measurement mode;
Measuring means for measuring optical characteristics of the test lens;
Storage means for storing results obtained by the measurement means;
Based on the result obtained by the measuring means, a first guiding means for guiding the progressive portion of the lens to be measured on the optical axis of the measuring light beam in the measuring means;
Second guiding means for guiding a distance portion of the lens to be measured on an optical axis of the measurement light beam in the measurement means;
Third guiding means for guiding the near portion of the lens to be measured on the optical axis of the measurement light beam in the measurement means ;
Among the sides of the deformed quadrangle formed by the measurement light beam being refracted according to the refraction characteristics of the test lens after passing through four points located at each corner of the quadrangle on the test lens, The length of the side located on the distance portion side: Lx1 and the length of the side located on the near portion side: Lx2 The difference value: Lx1-Lx2 is set as the progressive amount: P, and this progressive amount: P is set as the value. A progressive amount calculating means for obtaining the measurement light beam based on a detection result of the light receiving means;
Measurement point position distinguishing means for distinguishing whether the measurement point belongs to the progressive part, the distance part, or the near part, using the value of the progressive amount P obtained by the progressive amount computing means;
And characterized in that it comprises Renzume data. With vertical represent horizontal direction the prism amount represents a progressive amount, than the value of the progressive amount it can be determined that the value of the prism amount at 0 position in the horizontal direction is the progressive portion in 0 position of zero and a vertical direction A first guidance coordinate display means for displaying the set alignment coordinates on the display screen;
Each value of the prism amount and the progressive amount at the measurement position of the optical characteristic in the lens to be measured is obtained based on the detection value detected by the light receiving means with respect to the measurement light beam, and the first value is displayed on the display screen. The first guidance means is configured to include a first target display means for displaying a relative position with respect to each 0 position in the coordinates for alignment displayed by the guidance coordinate display means. By aligning the target displayed by the first target display means on the display screen with the center of the alamante coordinates displayed by the first guidance coordinate display means, Renzume data according to claim 1 which is adapted to be able to lead to the progressive portion of the lens. After the measurement point is guided to the progressive portion of the test lens by the first guiding means, an arrow indicating the direction in which the test lens is moved to guide the measurement point to the distance portion is displayed on the display screen. It includes means for displaying, Renzume data according to claim 1 or 2, wherein the second directing means is configured. With vertical represent horizontal direction the prism amount represents a progressive amount, following the progressive amount of value that can be determined that the value of the prism amount at 0 position in the horizontal direction is the distance portion at 0 position of zero and a vertical direction Coordinate display means for second guidance for displaying the coordinates for alignment set in the above on the display screen;
Based on the detection value detected by the light receiving means for the measurement light beam, each value of the prism amount and the progressive amount at the measurement position of the optical characteristic in the lens to be measured is obtained, and the second value is displayed on the display screen. The second guidance means is configured to include a second target display means for displaying a relative position with respect to each 0 position in the coordinates for alignment displayed by the guidance coordinate display means. By aligning the target displayed by the second target display means on the display screen with the center of the coordinates for the alamante displayed by the second guidance coordinate display means, Renzume data according to any one of claims 1 to 3 is adapted to be able to direct the distance portion of the lens. An arrow indicating a direction in which the test lens is moved to guide the measurement point to the near portion on the display screen after the measurement point is guided to the distance portion of the test lens by the second guiding means. It includes means for displaying, Renzume data according to any one of claims 1 to 4 wherein the third guide means is constituted. And displays the target to be moved in the vertical direction on the screen of the display in response to the measured position diopter seeking value magnitude of the diopter of the optical properties in the subject lens by the pre-Symbol measuring means, The measuring means obtains the value of the cylindrical refractive power at the measurement position of the optical characteristic of the lens to be measured, and the value of the cylindrical refractive power obtained by the measuring means at the distance portion guided by the second guiding means. Third target display means for obtaining a calculated value that is substantially zero in the progressive zone based on the difference from the value, and adjusting the position of the target in the horizontal direction on the display screen based on the value of the calculated value;
With reference to the value of the progressive amount obtained by the progressive amount calculation means at the measurement position of the optical characteristic in the test lens, the measurement position in the case where the measurement position is greater than or equal to the value of the progressive amount that can be determined to be a progressive portion. and display the shape of the target on the display screen of such a measuring position and a display shape of the target on the screen of the display when less than the value of the progressive amount that can be determined as a progressive portion, the target display to vary The third guiding means is configured including a shape changing means, and the target displayed by the third target display means is aligned on the horizontal center on the display screen, By moving the test lens until the display shape of the target changes from the display shape of the progressive part to the display shape of the near part, Renzume data according to any one of claims 1 to 5 that guides the fixed point in the near portion of該被subject lens is made to be able. The first guide means guides the progressive portion of the test lens onto the optical axis of the measurement light beam by guiding the optical center of the test lens onto the optical axis of the measurement light beam. Renzume data according to any one of 6.

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