Lens centering laser edge trimmer

Abstract

A lens centering laser edge trimmer is characterized in that a lens is fixed to a connector after being subjected to centering adjustment, a laser head is installed on a truss, the laser head and the lens can do relative translation in the two-dimensional direction in the plane perpendicular to the axis of the lens, the edge of the lens is cut by a laser beam, the outer edge of the lens is removed after a lens splitting process, and therefore centering edge cutting is achieved. The laser cutting head is used for replacing a grinding wheel for mechanically grinding the outer edge of the lens in a traditional centering edge grinding machine, the cutting efficiency is high, the cutting face quality is good, a mechanical centering method or an optical centering method can be adopted for centering, the equipment structure can be vertical or horizontal, the design scheme is flexible, and good application prospects are achieved.

Description

Technical Field

[0001] The present invention relates to optical lens processing technology, and particularly to a device with a lens centering function for laser cutting the outer edge of a lens. Background Art

[0002] For the processing of optical lenses, centering and edging (also called core cutting) is a basic process. Most lenses with a circular light-transmitting cross-section need to be centered and edged. While obtaining the required outer diameter, the line connecting the centers of the two end faces of the lens should be made to coincide with the mechanical axis as much as possible to control eccentricity.

[0003] There are various curved surface shapes of lenses, such as double convex, plano concave, meniscus, etc. As Figure 1 shown, in order to perform centering and edging on lens 1, a traditional centering and edging machine clamps lens 1 on the end faces on both sides of the lens respectively with joints (or chucks) 3 having an elastic pressing function along the axis. The machine tool axis 2 drives joints 3 and lens 1 to rotate along the axis, and a grinding wheel 4 is used to grind the outer cylinder of lens 1. If lens 1 has a suitable clamping angle (usually more than 12°), mechanical centering can generally be used. If lens 1 cannot provide a suitable clamping angle, an optical centering method can also be used (depending on the display method or light source characteristics, it is also called television centering method, laser centering method, etc., all belonging to optical centering). By observing the jump amount of the image point from the axis through a reflection optical path or a transmission optical path, after adjusting the attitude of the lens to be ground according to the jump amount, edging is then carried out. The head structure of joint 3 in contact with lens 1 is usually made into a metal tube shape. The above content can be seen in the optical processing technology manual.

[0004] Laser cutting of glass is a modern process and has replaced traditional mechanical grinding processes in many cases. Laser cutting equipment mostly uses fiber lasers, and there are various specifications for fiber lasers, such as wavelengths in the near-infrared, visible light, or near-ultraviolet ranges, pulse widths in picoseconds or femtoseconds, and powers in the watt to hundred-watt ranges. There are two common schemes for laser cutting of optical glass. One is to directly ablate and vaporize the glass material on the set path to form a cut, separating the required part (lens) from the unnecessary part. The other scheme is to punch out a row of fine holes with diameters and spacings in the micron range along the set path, and then perform a "chip breaking" operation to obtain the required lens. Summary of the Invention

[0005] The applicant believes that laser cutting technology can be applied to traditional lens centering and edging machines, that is, transplanting a laser cutting head onto a traditional lens centering and edging machine to replace the grinding wheel mechanism of the traditional centering and edging machine, and using laser ablation (and chip breaking) of the outer edge of the lens to achieve "edging" to manufacture a lens centering laser cutting machine.

[0006] The specific content of the invention is as follows:

[0007] Lens centering laser edge cutting machine, characterized in that after centering adjustment, the lens 1 is fixed on the joint 3, the laser head 5 is installed on the truss 6, the laser beam emitted by the laser head 5 is parallel to or forms a certain angle with the axis of the lens 1, the laser head 5 can be translated along the axis direction of the laser beam, and the laser head 5 and the lens 1 can perform relative translation in two dimensions in a plane perpendicular to the axis of the lens 1, and the edge of the lens 1 is cut by the laser beam to perform centering edge cutting on the lens 1.

[0008] Further, after centering adjustment, the lens 1 is fixed on the joint 3, characterized in that mechanical centering method or optical centering method is used for centering adjustment, and the optical centering method includes reflection optical path centering method or transmission optical path centering method.

[0009] Further, the laser beam emitted by the laser head 5 is parallel to or forms a certain angle with the axis of the lens 1, characterized in that the axis of the lens 1 is horizontally arranged, that is, the lens centering laser edge cutting machine is of horizontal structure, or the axis of the lens 1 is vertically arranged, that is, the lens centering laser edge cutting machine is of vertical structure.

[0010] Further, the edge of the lens 1 is cut by the laser beam to perform centering edge cutting on the lens 1, characterized in that the method of laser ablation slit or the method of laser punching a series of dots and then splitting are used to remove the edge of the lens 1.

[0011] Preferably, after centering adjustment, the lens 1 is fixed on the joint 3, characterized in that the joint 3 uses vacuum adsorption method to fix the lens 1.

[0012] Preferably, the laser head 5 is installed on the truss 6, characterized in that the laser head 5 is the output end of a fiber laser, the wavelength of the fiber laser is near infrared, visible light or near ultraviolet, the pulse width is picosecond level or femtosecond level, and the power is from watt level to hundred watt level. Beneficial effects

[0013] The lens centering laser edge cutting machine disclosed in this application is a transformation of the traditional centering edging machine by applying modern laser cutting technology. Compared with the prior art, the beneficial effects that can be obtained are:

[0014] The laser cuts with a beam, without mechanical contact between the grinding wheel and the lens in the traditional edging machine, with high cutting efficiency and good quality of the cutting section (edging), and can meet the quality requirements in terms of dimensional accuracy, cylindrical surface quality, chipping, etc.;

[0015] Centering can use mechanical centering method or optical centering method, the equipment structure can be vertical or horizontal, the design scheme is flexible, the processed lens can use vacuum adsorption or traditional clamping, wax sticking and other methods, the operation is simple, and it has good application prospects. Description of the drawings

[0016] Figure 1 It is a schematic diagram of the principle of a traditional mechanical centering grinding wheel edge grinding machine;

[0017] Figure 2 It is a schematic diagram of a mechanical centering vertical laser edge cutting machine;

[0018] Figure 3 It is a schematic diagram of a reflective optical centering vertical laser edge cutting machine;

[0019] Figure 4 It is a schematic diagram of a reflective optical centering vertical laser edge cutting machine;

[0020] Figure 5 It is a schematic diagram of a reflective optical centering vertical laser edge cutting machine;

[0021] Figure 6 It is a schematic diagram of a transmissive optical centering horizontal laser edge cutting machine;

[0022] Figure 7 It is a schematic diagram of the output beam of the laser head making a certain angle with the axis of the lens.

[0023] In the figure: 1. Lens, 2. Driving rotating shaft, 3. Connector, 4. Grinding wheel, 5. Laser head, 6. Truss, 7. Vacuum extraction pipe, 8. Reflector, 9. Centering imaging mechanism, 10. Light source, 11. Display, 12. Vertical plate, 13. Chassis. Specific embodiments

[0024] The following further details the present application in conjunction with the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only for explaining the present application and not for limiting the present application, and the schematic diagrams are not drawn in proportion to the actual objects.

[0025] Figure 2 It is a schematic diagram of a mechanical centering vertical laser edge cutting machine. "Vertical" means that the axes of the lens 1, the connector 3 and the driving rotating shaft 2 are vertically arranged (if the axis of the lens is horizontally arranged, it is called horizontal). The lens 1 is clamped and elastically pressed tightly by the connector 3 from both the upper and lower directions. The driving rotating shaft 2 drives the connector 3 and the lens 1 to rotate around the axis, and the driving motor can be arranged below the chassis 13 (not shown in the figure).

[0026] Figure 2 In it, the laser head 5 emits a laser beam from top to bottom, ablates a slit or drills a series of holes (subsequently splitting the pieces) at the edge of the lens 1 to achieve the "edge grinding" function. The direction of the laser beam is parallel to the axis direction of the lens 1. The laser head 5 is installed on the truss 6 and can move up and down (Z-axis) to find a suitable "focusing" position. The laser head 5 can move horizontally (X-axis and Y-axis) under the drive of the truss screw rod, that is, in a plane perpendicular to the lens 1, making a relative translational movement with the lens 1 in two dimensions, which is equivalent toFigure 1 The feeding and retracting of the grinding wheel 4, so that the laser head 5 makes three-dimensional translational movements while the chassis 13 does not need to move. The truss 6 can be installed on the chassis 13 or on a larger equipment base (not shown in the figure).

[0027] Figure 2 The problem of the embodiment is that when the size of the lens 1 is small, the laser head 5 may have a structural interference with the mechanical components above the lens 1. Therefore Figure 3 The embodiment adopts an optical centering method. The principle of the optical centering method is to observe the jump amount of the image point from the axis through the reflection optical path or the transmission optical path, and adjust the attitude of the lens to be ground according to the jump amount. Figure 3 Adopting the reflection optical path, the light emitted by the light source 10 passes through the centering imaging mechanism (the internal optical structure and principle are not described in detail) 9 and the mirror 8 and hits the surface of the lens 1 to be processed. The reflected light spot image is displayed on the display 11, so that Figure 2 The possible structural interference of the embodiment can be avoided.

[0028] Only one joint 3 for fixing the lens 1 is left at the bottom. The traditional method of fixing the lens 1 by the joint 3 is to use wax, rosin or glue, which can be adjusted for the attitude of the lens 1 when softened by heating, and can be used for edge grinding operation after hardening. Figure 3 Another method is provided, that is, the vacuum adsorption method. The inside of the tubular joint 3 is evacuated by the evacuation tube 7, and the lens 1 can also be fixed for laser edge cutting operation. Figure 3 The evacuation tube 7 is drawn in the shape of a curved hose in the figure only for easy understanding. Specifically, it can be designed as an axial seal ring sleeve structure, which is not described in detail in this application.

[0029] Figure 4 The embodiment is a change to Figure 3 , the centering imaging mechanism 9 is also installed on the truss 6. The centering imaging mechanism 9 can also move up and down (Z-axis) to achieve optical centering and focusing. The laser head 5 and the centering imaging mechanism 9 do not make horizontal (X-axis and Y-axis) translational movements, but instead the chassis 13 below drives the lens 1 to make horizontal translation, and the same can achieve "in the plane perpendicular to the axis of the lens 1, the laser head 5 and the lens 1 make relative translational movements in two directions". For the lens 1, there are two working stations, that is, first complete the centering operation below the centering imaging mechanism 9 station, and then move to below the laser head station to complete the edge cutting operation of "driving in a circle" in the X and Y axes. Figure 4 One advantage of the embodiment is that the rotation driven by the motor may no longer be needed below the lens 1. The edge cutting action of "driving in a circle" is realized by the translational movement of the chassis 13, which can simplify the design of the vacuum device for the joint 3.

[0030] Figure 5In the embodiment, the optical path of the reflective optical centering is designed below the lens 1, so that the space above the lens is more open. As Figure 5 shown, the reflecting mirror 8 and the centering imaging mechanism 9 are both arranged below the chassis 13. The chassis does not perform translational motion, and the trimming action is realized by the three-dimensional translational motion of the laser head 5. The vacuum tube 7 at the joint 3 can be led out from the cylindrical surface of the joint 3, and the structural design is more convenient.

[0031] All the above embodiments provide vertical structures. If the axis of the lens 1 is set horizontally, it becomes a horizontal structure. As Figure 6 shown, the optical centering adopts a transmission optical path. The light emitted by the light source 10 is reflected and then enters the lens 1 to be processed, and the transmitted light is received by the centering imaging mechanism 9. Compared with the embodiment of the vertical structure, the original horizontal truss 6 is placed vertically, and the original chassis 13 is also erected and changed into a vertical plate 12, which is installed on the new chassis 13. It should be noted that the size of the vertical plate 12 should be large enough to ensure that the laser emitted by the laser head 5 at any position that can be moved on the truss 6 can be blocked by the vertical plate 12 and not shoot outside the device, ensuring the safety of the device during use.

[0032] Under normal circumstances, the lens edge grinding needs to form a cylindrical edge grinding surface. In special cases, when a conical edge grinding surface is required for the lens edge grinding, the above embodiments can be realized by adjusting the installation angle of the laser head 5 on the truss 6. As Figure 7 shown, the axis direction of the output laser beam of the laser head 5 is not parallel to the axis direction of the lens 1, but is set at a certain angle θ, so that a conical edge grinding surface can be cut out at the edge of the lens 1. Obviously, adjusting the installation angle of the laser head 5 on the truss 6 is much more convenient and simple than adjusting the mechanism of the high-speed rotating grinding wheel of the traditional edge grinder.

[0033] As can be seen from the above embodiments, the idea of the present application is to use the laser beam emitted by the laser head 5 to cut the edge of the lens 1, so as to replace the grinding wheel in the traditional centering edging machine. The transmission direction of the laser beam is parallel or at a certain angle to the axis direction of the lens 1. In terms of equipment design, the lens 1 to be processed can use mechanical centering or optical centering, and optical centering can use a reflection optical path or a transmission optical path; the lens 1 can be installed on the joint 3 by means of vacuum adsorption or bonding; the axis of the lens 1 can be set horizontally (horizontal equipment) or vertically (vertical equipment); in the direction along the laser beam axis, the laser head 5 can be translated to achieve the "focusing" of the laser beam, and in the plane perpendicular to the axis of the lens 1, the laser head 5 and the lens 1 can perform relative translation in two directions to achieve "feeding", "retracting" or "circling" actions; in terms of cutting process, either direct laser cutting or splitting after punching a series of holes can be selected (usually the punching series method is used for processing precision lenses, and the laser beam needs to be incident perpendicular to the surface of the lens 1); in addition, in terms of laser characteristics, the laser head 5 is preferably the output end of a fiber laser, the wavelength of the fiber laser is near-infrared, visible light or near-ultraviolet, the pulse width is picosecond or femtosecond level, and the power is in the range of watts to hundreds of watts. The laser head 5 can also be the output end of other types of lasers (such as gas lasers, solid lasers, etc.), and there are various choices for the type of laser and the beam characteristics.

[0034] The above are only the preferred embodiments of the present application and the technical principles applied. For those skilled in the art, without departing from the inventive concept of the present invention, more other equivalent embodiments can be generated, and the protection scope of the present invention is determined by the scope of the appended claims.

Claims

1. Lens centering laser edge cutting machine, characterized in that, The lens (1) is fixed on the connector (3) after centering adjustment. The laser head (5) is installed on the truss (6). The laser beam emitted by the laser head (5) is parallel to the axis of the lens (1) or forms a certain angle therewith. The laser head (5) can be translated along the axis direction of the laser beam. The laser head (5) and the lens (1) can perform relative translation in two-dimensional directions in a plane perpendicular to the axis of the lens (1). The edge of the lens (1) is cut by the laser beam to perform centering edge cutting on the lens (1).

2. The lens centering laser edge cutting machine according to claim 1, wherein Mechanical centering method or optical centering method is used for centering adjustment. The optical centering method includes reflective optical path centering method or transmissive optical path centering method.

3. The lens centering laser edge cutting machine according to claim 1, wherein The axis of the lens (1) is set horizontally, that is, the lens centering laser edge cutting machine is of horizontal structure, or the axis of the lens (1) is set vertically, that is, the lens centering laser edge cutting machine is of vertical structure.

4. The lens centering laser edge cutting machine according to claim 1, characterized in that, The edge of the lens (1) is removed by the method of laser ablation slitting or by the method of laser dotting followed by chipping.

5. The lens centering laser edge cutting machine according to claim 1, wherein, The connector (3) uses vacuum adsorption to fix the lens (1).

6. The lens centering laser edge cutting machine according to claim 1, characterized in that, The laser head (5) is the output end of a fiber laser. The wavelength of the fiber laser is near-infrared, visible light or near-ultraviolet, the pulse width is picosecond level or femtosecond level, and the power is in the range of watts to hundreds of watts.

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