Automatic focusing lensometer

Abstract

The utility model relates to a lens detection field especially relates to an automatic focusing formula lensmeter, including frame and install illumination light source, axial position adjusting subassembly, focusing subassembly, lens support, imaging subassembly, industrial computer on the frame, corneal contact lens is placed on the lens support, axial position adjusting subassembly includes the scale plate and drives the axial position drive mechanism that scale plate rotates, focusing subassembly includes focusing lens group and drives the focusing drive mechanism that focusing lens group removes, imaging subassembly includes imaging lens group and camera, and industrial computer is used for respectively to focusing drive mechanism and axial position drive mechanism control. The utility model realizes the automatic regulation of focusing amount and axial position through axial position adjusting subassembly and focusing subassembly, and then adjusts the projection pattern of corneal contact lens to be most clear, avoids the reading error that the artificial interpretation brings, and has improved the repeat measurement accuracy.

Description

Technical Field

[0001] This utility model belongs to the field of lens testing technology, and in particular relates to an automatic focusing focimeter. Background Technology

[0002] A focimeter is an instrument used to measure the refractive power and axis of a corneal contact lens. There are two main types. One is the manual focusing focimeter. The operator places the contact lens in the testing area and manually rotates the focusing wheel and axis wheel until the image on the projection glass is clearest. The refractive power and axis of the contact lens can then be calculated based on the positional changes of the focusing and axis wheels. The disadvantage of the manual focusing focimeter is that it requires manual operation of the focusing and axis wheels, and the clarity of the projected image relies on subjective judgment. Different people perceive when the projected image is clearest differently, and even the same person's perception can vary at different times, leading to significant human error. Furthermore, due to the optical principle of projection measurement, the operator is essentially looking directly at the light source, which can irritate the operator's eyes during prolonged use. The other type is the automatic focusing focimeter, which calculates the light refraction based on Hartmann's principle and can directly obtain the refractive power and axis of the contact lens. The disadvantage of autofocus focimeters is that they do not have an intuitive reticle projection pattern. They can only measure the refractive power and axis of the contact lens and cannot judge the image quality of the contact lens. For example, if there are defects such as bubbles or contamination on the contact lens, the autofocus focimeter cannot detect these problems. Utility Model Content

[0003] In view of this, the present invention aims to provide an autofocus focimeter to solve the technical problem that manual focus focimeters have large errors in the detection results due to subjective judgment, and that autofocus focimeters cannot judge the imaging quality of corneal contact lenses.

[0004] To achieve the above objectives, the technical solution created by this utility model is implemented as follows: An automatic focusing focimeter includes a frame and, in accordance with the direction of light propagation, an illumination source, an axis adjustment assembly, a focusing assembly, a lens support, an imaging assembly, and an industrial control computer mounted on the frame; wherein... The corneal contact lens is placed on the lens holder; The axis adjustment assembly includes a reticle and an axis drive mechanism that drives the reticle to rotate; The focusing assembly includes a focusing lens group and a focusing drive mechanism that moves the focusing lens group. The imaging components include an imaging lens group and a camera; The industrial control computer is used to control the focusing drive mechanism and the shaft position drive mechanism respectively.

[0005] Furthermore, the shaft drive mechanism includes a shaft motor, a shaft drive gear, a shaft driven gear, a shaft adjusting gear, a reticle mounting base, a shaft encoder, a shaft motor mounting plate, and a shaft encoder mounting plate. The shaft motor is fixed to the frame via the shaft motor mounting plate, and the shaft encoder is fixed to the frame via the shaft encoder mounting plate. The shaft drive gear is mounted on the output shaft of the shaft motor, and the shaft driven gear is mounted on the rotating shaft of the shaft encoder. The reticle is mounted on the reticle mounting base, and the reticle mounting base is fixed to one side of the shaft adjusting gear. Both the shaft adjusting gear and the shaft driven gear mesh with the shaft drive gear for transmission.

[0006] Furthermore, the focusing drive mechanism includes a focusing motor, a focusing motor mounting plate, a coupling, a drive shaft, a helical gear, a helical rack, a sliding plate, a focusing drive gear, a focusing driven gear, a focusing encoder, and a focusing encoder mounting plate. The focusing motor is fixed to the frame via the focusing motor mounting plate, and the focusing encoder is fixed to the frame via the focusing encoder mounting plate. The output shaft of the focusing motor is connected to one end of the drive shaft via the coupling. The focusing drive gear is mounted on the other end of the drive shaft. The focusing driven gear is mounted on the rotating shaft of the focusing encoder and meshes with the focusing drive gear for transmission. The helical gear is mounted in the middle of the drive shaft and meshes with the helical rack for transmission. The helical rack is fixed to one side of the sliding plate, and the focusing lens assembly is fixed to the other side of the sliding plate via a connecting plate.

[0007] Furthermore, the focusing drive mechanism also includes a linear guide rail, which includes a guide rail and a slider. The guide rail is fixedly connected to the frame, and the slider slides on the guide rail and is fixedly connected to the side of the sliding plate opposite to the helical rack.

[0008] Furthermore, the autofocus focimeter also includes a display screen and a touch screen, which are connected to the industrial computer respectively.

[0009] Compared with the prior art, the present invention can achieve the following beneficial effects: (1) The focusing amount and axis are automatically adjusted by the axis adjustment component and the focusing component, thereby adjusting the projection pattern of the corneal contact lens to the clearest, avoiding human subjective interpretation error, making the measurement results more accurate and the measurement efficiency high. (2) While measuring the refractive power and axis of the corneal contact lens, the display screen can display the projection pattern of the corneal contact lens taken by the camera in real time, which makes it easy to observe whether there are any defects in the corneal contact lens. (3) Operators only need to observe the display screen and do not need to look directly at the lighting source for a long time, thus protecting the operator's eyesight. Attached Figure Description

[0010] The accompanying drawings, which form part of this invention, are used to provide a further understanding of this invention. The illustrative embodiments and descriptions of this invention are used to explain this invention and do not constitute an undue limitation of this invention. In the drawings: Figure 1 This is a schematic diagram of the structure of the automatic focusing focimeter according to the embodiments of this utility model; Figure 2 This is a schematic diagram of the shaft drive mechanism according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the focusing drive mechanism according to an embodiment of the present invention; Figures 4a-4c This is a schematic diagram illustrating the measurement effect of the posterior vertex focal length according to an embodiment of the present invention; Figures 5a-5c This is a schematic diagram illustrating the change of the sharpness value calculation position with axis position according to the embodiment of this utility model.

[0011] The reference numerals in the accompanying drawings include: frame 1, lighting source 2, shaft position adjustment assembly 3, reticle 301, shaft position motor 302, shaft position drive gear 303, shaft position driven gear 304, shaft position adjustment gear 305, reticle mounting base 306, shaft position encoder 307, shaft position motor fixing plate 308, shaft position encoder fixing plate 309, focusing assembly 4, focusing lens group 401, focusing motor 402, focusing motor fixing plate 403, coupling 404, drive shaft 405, helical gear 406, helical rack 407, sliding plate 408, focusing drive gear 409, focusing driven gear 410, focusing encoder 411, focusing encoder fixing plate 412, linear guide rail 413, lens support 5, imaging assembly 6, industrial computer 7, display screen 8, touch screen 9, angle adjustment bracket 10. Detailed Implementation

[0012] To make the purpose, technical solution, and advantages of this utility model clearer, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this utility model and do not constitute a limitation thereof.

[0013] It should be noted that, without conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0014] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0015] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0016] The following will refer to Figures 1-5c The present invention will be described in detail with reference to the embodiments.

[0017] like Figures 1-3As shown, the automatic focusing focimeter provided in this embodiment of the invention includes a frame 1 and an illumination source 2, an axis adjustment assembly 3, a focusing assembly 4, a lens support 5, an imaging assembly 6, and an industrial control computer 7, a display screen 8, and a touch screen 9, all mounted sequentially on the frame 1 according to the light propagation direction. A contact lens is placed on the lens support 5. The axis adjustment assembly 3 includes a reticle 301 and an axis drive mechanism that rotates the reticle 301. The reticle 301 has two crosshairs for calculating the refractive power and axis of the contact lens. The focusing assembly 4 includes a focusing lens group 401. The system includes a focusing drive mechanism that moves the focusing lens group 401; the imaging assembly 6 includes an imaging lens group and a camera, the imaging lens group being used to image the corneal contact lens, and the camera being used to acquire images of the corneal contact lens; the industrial control computer 7 is used to control the focusing drive mechanism and the axis drive mechanism respectively, and to calculate the refractive power and axis of the corneal contact lens; the display screen 8 and the touch screen 9 are respectively connected to the industrial control computer 7; the display screen 8 is mounted on the frame 1 via the angle adjustment bracket 10, and is used to realize human-machine interaction; the touch screen 9 is used to trigger measurement commands and display images acquired by the camera; the display screen 8 is used to display the acquired images.

[0018] Images captured by the camera can be displayed on either the small touchscreen 9 or the larger display screen 8, making it easier for more people to view them.

[0019] The shaft drive mechanism 3 includes a shaft motor 302, a shaft drive gear 303, a shaft driven gear 304, a shaft adjusting gear 305, a reticle mounting base 306, a shaft encoder 307, a shaft motor mounting plate 308, and a shaft encoder mounting plate 309. The shaft motor 302 is fixed to the frame 1 via the shaft motor mounting plate 308, and the shaft encoder 307 is fixed to the frame 1 via the shaft encoder mounting plate 309. The shaft drive gear 303 is mounted on the output shaft of the shaft motor 302, and the shaft driven gear 304 is mounted on the rotating shaft of the shaft encoder 307. The reticle 301 is mounted on the reticle mounting base 306, and the reticle mounting base 306 is fixed to one side of the shaft adjusting gear 305. Both the shaft adjusting gear 305 and the shaft driven gear 304 mesh with the shaft drive gear 303 for transmission.

[0020] The shaft position motor 302 drives the shaft position drive gear 303 to rotate, which in turn drives the shaft position driven gear 304 and the shaft position adjusting gear 305 to rotate. The shaft position driven gear 304 drives the shaft position encoder 307 to rotate, and the shaft position adjusting gear 305 drives the reticle 301 to rotate, ultimately causing the image displayed on the display screen 8 and the touch screen 9 to rotate, thus achieving the purpose of adjusting the shaft position.

[0021] When measuring the axis of a contact lens, the contact lens is placed on the lens support 5. Illumination light from the illumination source 2 passes sequentially through the reticle 301, the contact lens, the focusing lens group 401, and the imaging lens group, finally forming an image on the camera target surface. The image is then displayed on the display screen 8 and the touch screen 9 via the industrial control computer 7. By operating the touch screen 9, an axis measurement command is issued, which drives the axis adjustment by the axis motor 302. The position of the clearest image is determined from the image captured by the camera. The code value of the axis encoder 307 provides feedback on the position of the axis motor 302 when the image is clearest, thereby calculating the axis of the contact lens.

[0022] The focusing drive mechanism includes a focusing motor 402, a focusing motor mounting plate 403, a coupling 404, a transmission shaft 405, a helical gear 406, a helical rack 407, a sliding plate 408, a focusing drive gear 409, a focusing driven gear 410, a focusing encoder 411, a focusing encoder mounting plate 412, and a linear guide rail 413. The focusing motor 402 is fixed to the frame 1 via the focusing motor mounting plate 403, and the focusing encoder 411 is fixed to the frame 1 via the focusing encoder mounting plate 412. The output shaft of the machine 402 is connected to one end of the transmission shaft 405 via a coupling 404. The focusing drive gear 409 is mounted on the other end of the transmission shaft 405. The focusing driven gear 410 is mounted on the rotating shaft of the focusing encoder 411 and meshes with the focusing drive gear 409 for transmission. The helical gear 406 is mounted in the middle of the transmission shaft 405 and meshes with the helical rack 407 for transmission. The helical rack 407 is fixed on one side of the sliding plate 408. The focusing lens assembly 401 is fixed on the other side of the sliding plate 408 via a connecting plate.

[0023] The linear guide rail 413 includes a guide rail and a slider. The guide rail is fixedly connected to the frame 1, and the slider slides on the guide rail and is fixedly connected to the side of the sliding plate 408 opposite to the helical rack. The linear guide rail 413 is used to ensure the linearity of the up and down movement of the sliding plate 408, thereby ensuring the focusing effect of the focusing lens group 401.

[0024] The focusing motor 402 drives the transmission shaft 405 to rotate, which in turn drives the helical gear 406 and the focusing drive gear 409 to rotate. The focusing drive gear 409 drives the focusing driven gear 410 to rotate, which in turn drives the focusing encoder 411 to rotate. The helical gear 406 drives the sliding plate 408 to move up and down, which in turn drives the focusing lens group 401 to move up and down, thus achieving focusing.

[0025] When measuring the refractive power of a contact lens, the contact lens is placed on the lens holder 5. Illumination light from the illumination source 2 passes sequentially through the reticle 301, the contact lens, the focusing lens group, and the imaging lens group, finally forming an image on the camera target surface. This image is then displayed on the display screen 8 and the touch screen 9 via the industrial control computer 7. By operating the touch screen 9, a refractive power measurement command is issued, driving the focusing motor 402 to adjust the focus. The camera captures images throughout its entire stroke. After acquiring all images, the image with the highest sharpness value is selected as the clearest image position. The focusing motor 402 then rotates to that position to obtain the clearest image. The focusing encoder 411 provides feedback on the position of the focusing motor 402 when the image is clearest, and the corresponding vertex power value at that position is calculated.

[0026] The industrial computer 7 uses the XCY-X30A-N2930 model product from Xinchuangyun Company, the display screen 8 uses the 8-inch IPS TFT LCD model product from Pingxian Technology Company, and the touch screen 9 uses the DC32960M046_1010_0X(CN) model product from Dacai Technology Company.

[0027] The autofocus focimeter provided in this invention can measure the refractive power and axis of a contact lens. The refractive power includes the posterior vertex power (myopia) and the cylindrical power (astigmatism), and the axis is also known as the astigmatic axis. The autofocus focimeter can measure only the posterior vertex power of the contact lens, or it can simultaneously measure the posterior vertex power, cylindrical power, and axis of the contact lens.

[0028] When measuring only the posterior vertex power of a corneal contact lens, the measurement method is as follows: A1: Place the contact lens on the autofocus lens holder.

[0029] The operator begins the measurement by clicking on the touchscreen.

[0030] A2: The industrial control computer controls the focusing motor to return to the negative limit position, and at the same time controls the shaft position motor to return to the 0-degree position.

[0031] A3: The industrial control computer controls the camera to acquire images of the corneal contact lens and calculates the sharpness value of a crosshair position on the reticle in the image.

[0032] A4: The industrial control computer controls the focusing motor to move at high speed from the negative limit position to the positive limit position, and at the same time records the position of the focusing motor and the sharpness value to obtain the relationship between the sharpness value and the position of the focusing motor. When the sharpness value is at its maximum value, the position P1 corresponding to the focusing motor is the approximate value of the back top focus.

[0033] The sharpness value is calculated as follows: Let the image size be x×y pixels, and the difference calculation range be m×n pixels, then the sharpness difference value... ,in These are the RGB channel values ​​of the pixel at positions x and y. The RGB channel values ​​of the pixels at x+i and y+j, for example, P(101 201)=(128 0 255) refers to pixels (101) The RGB channel values ​​at position 201 are 128, 0, and 255. (This is the result of obtaining...) Afterwards, The sharpness value is obtained by summing the values ​​of the RGB channels, that is, by adding the values ​​of the three RGB channels together.

[0034] The focusing motor moves at a high speed of 80° / s and at a low speed of 28° / s.

[0035] Since the posterior vertex power value in the focimeter is linearly related to the position of the focusing motor, the correspondence between the posterior vertex power value and the position of the focusing motor can be obtained through prior calibration. Therefore, the actual measurement during measurement is of the position of the focusing motor. Then, the posterior vertex power value of the corneal contact lens is obtained through the correspondence between the posterior vertex power value and the position of the focusing motor.

[0036] like Figures 4a-4c As shown, the measurement effect of the posterior vertex focal length is from Figures 4a-4c The categories are, in order: clear, somewhat blurry, and very blurry. Figures 4a-4c The yellow box in the middle represents the area where the sharpness value is calculated. Figures 4a-4c The calculated sharpness values ​​are 81930, 36080, and 19526, respectively. The higher the sharpness, the clearer the image.

[0037] A5: The industrial control computer controls the focusing motor to move at high speed from the positive limit position to the position of P1+10% of the total stroke of the focusing motor, and then controls the focusing motor to move at low speed to the position of P1-10% of the total stroke of the focusing motor. The relationship between the sharpness value and the position of the focusing motor is obtained. When the sharpness value is at its maximum value, the position P2 corresponding to the focusing motor is the accurate value of the back top focal length measurement.

[0038] When simultaneously measuring the posterior vertex power, cylindrical power, and axis of a corneal contact lens, the measurement method is as follows: B1: Place the contact lens on the autofocus lens holder.

[0039] B2: The industrial control computer controls the focusing motor to return to the negative limit position, and at the same time controls the shaft position motor to return to the 0-degree position.

[0040] B3: The industrial control computer controls the camera to acquire images of the corneal contact lens and calculates the sharpness value of a crosshair position on the reticle in the image.

[0041] B4: The industrial control computer controls the axis position motor to rotate from a negative angle position to a positive angle position at a preset step interval. During each rotation of the axis position motor, the industrial control computer controls the focusing motor to move at high speed from the limit position to the positive limit position, thereby obtaining the relationship between the sharpness value of each axis position and the position of the focusing motor. , This is the sharpness value. For axis position, Position of the focusing motor; when At its maximum, the approximate position of the shaft and the focusing motor is obtained. , .

[0042] B5: with , The total stroke of the focusing motor is within a certain range. The focusing motor moves at low speed, and the stepping interval of the shaft position motor is 0.5 degrees. Repeat step B4 to measure the precise position of the shaft position and the focusing motor. , .

[0043] B6: In With the axis in place, repeat steps A4 and A5 to measure the sharpness value at the other crosshair position of the reticle, and obtain the position of the focusing motor when the sharpness value is maximum. Then the posterior vertex power of the corneal contact lens is Cylindrical focal length The axis is .

[0044] like Figures 5a-5c As shown, Figure 5a The calculation area for sharpness values ​​at a 30-degree axis position; Figure 5b The calculation area for sharpness values ​​at a -10 degree axis position; Figure 5c The area for calculating the sharpness value of another crosshair after determining the axis position.

[0045] The measurement methods for the refractive power and axis of the aforementioned contact lens are the same as those used in existing autofocus focimeters. Therefore, the program corresponding to the method for calculating the refractive power and axis of the contact lens using an industrial control computer is an existing program embedded in the industrial control computer. The improvement of this invention lies in the automatic adjustment of the axis and focal point through the design of the axis drive mechanism and the focusing drive mechanism. Automated adjustment can accurately determine the clearest projection pattern of the reticle, avoiding subjective judgment and unnecessary human error compared to the manual adjustment of a manual focusing focimeter. Compared to an autofocus focimeter, this invention can image the reticle through the imaging lens group, allowing for the assessment of the contact lens's image quality and the detection of surface defects and flaws on the contact lens. Therefore, the improvement of this invention lies not in how to calculate the refractive power and axis of the contact lens, but in the structural design of the axis drive mechanism and the focusing drive mechanism.

[0046] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this utility model disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this utility model can be achieved, and this is not limited herein.

[0047] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. An automatic focusing focimeter, characterized in that, It includes a frame and, in sequence along the light propagation direction, an illumination source, an axis adjustment assembly, a focusing assembly, a lens support, an imaging assembly, and an industrial control computer mounted on the frame; among which... The contact lens is placed on the lens holder; The axis adjustment assembly includes a reticle and an axis drive mechanism that drives the reticle to rotate; The focusing assembly includes a focusing lens group and a focusing drive mechanism that moves the focusing lens group. The imaging components include an imaging lens group and a camera; The industrial control computer is used to control the focusing drive mechanism and the shaft position drive mechanism respectively.

2. The autofocus focimeter according to claim 1, characterized in that, The shaft drive mechanism includes a shaft motor, a shaft drive gear, a shaft driven gear, a shaft adjusting gear, a reticle mounting base, a shaft encoder, a shaft motor mounting plate, and a shaft encoder mounting plate. The shaft motor is fixed to the frame via the shaft motor mounting plate, and the shaft encoder is fixed to the frame via the shaft encoder mounting plate. The shaft drive gear is mounted on the output shaft of the shaft motor, and the shaft driven gear is mounted on the rotating shaft of the shaft encoder. The reticle is mounted on the reticle mounting base, which is fixed to one side of the shaft adjusting gear. Both the shaft adjusting gear and the shaft driven gear mesh with the shaft drive gear for transmission.

3. The autofocus focimeter according to claim 2, characterized in that, The focusing drive mechanism includes a focusing motor, a focusing motor mounting plate, a coupling, a drive shaft, a helical gear, a helical rack, a sliding plate, a focusing drive gear, a focusing driven gear, a focusing encoder, and a focusing encoder mounting plate. The focusing motor is fixed to the frame via the focusing motor mounting plate, and the focusing encoder is fixed to the frame via the focusing encoder mounting plate. The output shaft of the focusing motor is connected to one end of the drive shaft via the coupling. The focusing drive gear is mounted on the other end of the drive shaft. The focusing driven gear is mounted on the rotating shaft of the focusing encoder and meshes with the focusing drive gear for transmission. The helical gear is mounted in the middle of the drive shaft and meshes with the helical rack for transmission. The helical rack is fixed to one side of the sliding plate, and the focusing lens assembly is fixed to the other side of the sliding plate via a connecting plate.

4. The autofocus focimeter according to claim 3, characterized in that, The focusing drive mechanism also includes a linear guide rail, which includes a guide rail and a slider. The guide rail is fixedly connected to the frame, and the slider slides on the guide rail and is fixedly connected to the side of the sliding plate opposite to the helical rack.

5. The autofocus focimeter according to claim 1, characterized in that, It also includes a display screen and a touch screen, which are connected to the industrial computer respectively.

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