JP2004017166A - Aspheric lens polishing method and device using cam type sphere center type polisher - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a machining method for an aspheric lens embodying a locus of an aspheric surface using a cam type sphere center type polisher. <P>SOLUTION: The cam type sphere center type polisher is provided with a sphere center type cam wherein the locus of the mean curvature of an aspheric lens to be machined is the locus of a tool. The aspheric lens is machined by applying the locus of an aspheric surface to the machining tool by delivering or drawing the machining tool at each rocking angle with the difference of the mean curvature of the aspheric-lens to be machined and the locus of the machining tool. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing an aspheric lens having an axially symmetrical aspherical shape among optical aspheric lens processing methods, and more particularly, to an aspheric lens polishing method using a cam-type spherical core type polishing machine and a polishing apparatus therefor. Things.
[0002]
[Prior art]
Conventionally, a profile grinding device is known as an aspherical surface processing machine generally used. As a conventional polishing method, there is also known a method of dividing and polishing an aspheric lens using a forced rotation type polishing machine. Further, devices using a lathe or a cup type tool using numerical control are well known.
[0003]
Therefore, an aspherical surface processing method using numerical control and its processing apparatus will be described with reference to FIGS. This method and apparatus are disclosed in Japanese Patent Application Laid-Open No. 5-138521, entitled "Apparatus and Method for Creating Aspheric Surface". This conventionally known invention relates to an apparatus for generating an aspheric surface in an optical glass lens mold and the like and a method for generating the same, and the purpose thereof is to reduce the cutting amount of a grinding stone with respect to a processing lens by grinding or polishing an aspheric lens. The point is to increase the processing accuracy by reducing it. In this configuration, a tool rotating shaft portion 102 configured to be vertically movable as indicated by an arrow Z is mounted on a side wall surface of an upper end portion of an L-shaped frame 101 via a tool moving portion 103. A rotating shaft 104 that is rotated by a motor is provided at the tip of the tool rotating shaft 102, and an open plate-shaped processing tool 105 is mounted at the tip. In the frame 101 at a lower position opposed to the tool rotation shaft 102, a work shaft 106 having a front end arranged upward is suspended and mounted. The work shaft 106 is provided with a detachable 107 attached to the tip of a work shaft 108 provided on the shaft center, and the rotating shaft 108 on which the work 107 is mounted is rotated in the direction of arrow B by a motor. Work shank, the swinging of the arrow A to O ₁ points shown in the work 107 as a fulcrum, an arrow about a vertical work pivot shaft in the plane containing the Y axis vertical movement Z and workpiece shaft 106 of the tool 105 Y Directionally operative. That is, this conventional method is characterized in that an aspherical surface is created by controlling three axes of an angle axis (oscillation axis), a Z axis and a Y axis.
[0004]
[Problems to be solved by the invention]
Such an apparatus based on the prior art method is not only difficult to change the setup, but also unsuitable for small lots of other products. Since the reproducibility at the time of setup becomes difficult, reducing the number of divisions causes a problem that processing accuracy is deteriorated. Further, in the example of the aspherical processing machine using the numerical control, if the number of control axes is increased, the apparatus becomes expensive and the processing program becomes complicated.
[0005]
Therefore, the present invention has been developed in view of such a drawback, in which the machining tool swings around the spherical center of the pseudo spherical surface with respect to the aspherical shape, and further simulates the processing tool with a difference from the pseudo spherical surface. There is a problem to be solved by the present invention in that aspherical polishing is performed by correcting in the spherical center direction of a spherical surface.
[0006]
[Means for Solving the Problems]
The present invention has been developed in order to solve the problems as described above, and has been developed for an aspherical lens using a cam-type ball-center type polishing machine constituted by an oscillating body that rotates a polishing plate and oscillates a ball center. In the polishing method, a cam-type ball-center type polishing machine is characterized in that an aspherical trajectory control is given to a polishing plate by interpolating an angle between a table which can reciprocate on an axis passing through the center of the oscillator and the oscillator. The present invention provides a method of polishing an aspherical lens using a method, and further comprises a cam-type spherical core in which the shape of a polishing dish is a spherical surface having a curvature smaller than the minimum curvature portion of the curvature of the aspherical lens to be processed in the aspherical lens polishing method. In the provision of an aspheric lens polishing method using a polishing machine, it is possible to further turn the position at which the polishing dish comes into contact with the processed aspheric lens in the aspheric lens polishing method as the spherical center of the polishing dish. Cam type ball core type An aspheric lens polishing method using a polishing machine is provided. Further, in the above aspheric lens polishing method, the aspheric surface is polished by controlling two axes by using a cam instead of numerical control having three or more axes. An object of the present invention is to provide an aspheric lens polishing method using a cam-type ball-center type polishing machine.
[0007]
The present invention also provides a polishing apparatus for an aspheric lens using a cam-type spherical core type polishing machine constituted by an oscillator that rotates a polishing dish and swings a ball center, wherein an axis passing through the center of the oscillator is An aspherical lens polishing apparatus using a cam-type spherical core type polishing machine, comprising: a reciprocating table and a polishing plate for interpolating the angle of the oscillating body, and giving an aspherical trajectory control to the polishing plate. In addition, in the above-mentioned aspheric lens polishing apparatus, a trajectory of the average curvature of the curvature of the aspheric lens to be processed is provided with a spherical core type cam that is the trajectory of the tool, and the curvature of the aspheric lens to be processed and the processing tool The present invention provides an aspheric lens polishing apparatus using a cam-type spherical center polisher having an aspheric trajectory to the processing tool by extending or retracting the processing tool at each swing angle. is there.
[0008]
That is, first, a means for solving the problem of the present invention is to dispose a cam so that the spherical center of the pseudospherical surface of the aspherical lens to be processed and the oscillating spherical center of the processing tool coincide with each other, and perform machining at each angle. Reciprocate the tool to create an aspheric trajectory. In this case, the angle θ is θ = Tan ⁻¹ (X / Y), and the curvature of the pseudo spherical surface is R, and the feeding amount △ is calculated by △ = √ (X ² + Y ² ) −R. Therefore, the trajectory of the aspherical surface is created by interpolating the angle θ and the feeding amount △.
[0009]
Second, the manufacture of the tool plate is facilitated by using a spherical tool plate smaller than the minimum curvature of the lens to be processed.
[0010]
Third, the arrangement of the tool plate is such that it can be turned around the ball center of the tool plate, thereby facilitating the setup.
[0011]
Fourth, there is a need for facilitating the creation of a control program and reducing the processing cost.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention is directed to a method of polishing an aspheric lens using a cam-type spherical core type polishing machine including an oscillator that rotates a polishing plate and swings a ball center, wherein an axis passing through the center of the oscillator is provided. An aspheric lens polishing method using a cam-type spherical core type polishing machine, characterized by interpolating an angle between a table that can reciprocate on a line and the oscillating body and giving an aspheric trajectory control to the polishing dish, In the above-mentioned aspheric lens polishing method, there is provided an aspheric lens polishing method using a cam-type ball-center type polishing machine in which the shape of a polishing dish has a curvature of a spherical surface smaller than a minimum curvature portion of a curvature of a processed aspheric lens, and Aspherical lens polishing using a cam-type spherical center type polishing machine which enables a position where the polishing plate comes into contact with the aspherical lens to be processed to be rotated as a spherical center of the polishing plate in the above-mentioned aspherical lens polishing method. The method, and further Aspherical lens polishing method using a cam-type spherical core type polishing machine for polishing an aspherical surface by controlling two axes by using a cam instead of numerical control having three or more axes in the aspherical lens polishing method The aspherical surface can be easily polished by oscillating the processing tool around the spherical center of the pseudospherical surface with respect to the aspherical shape and correcting the processing tool to the spherical center of the pseudospherical surface with the difference from the pseudospherical surface. Can be done.
[0013]
Further, an embodiment of the present invention relates to an aspheric lens polishing apparatus using a cam-type spherical core type polishing machine constituted by an oscillator that rotates a polishing dish and swings a ball center, and passes through the center of the oscillator. An aspherical surface using a cam-type ball-center type polishing machine, comprising: a table capable of reciprocating on an axis and a polishing plate for interpolating the angle of the oscillating body, and giving an aspherical trajectory control to the polishing plate. A lens-centered cam provided in the lens polishing apparatus, wherein the trajectory of the average curvature of the aspheric lens to be processed is a tool trajectory in the aspheric lens polishing apparatus; And an aspheric lens polishing apparatus using a cam-type ball-center polisher having an aspheric trajectory given to the processing tool by extending or retracting the processing tool at each swing angle. From the angle θ and the feed amount Aspherical trajectory by interpolation can be created, and also the manufacture of the tool disc can be easily by using a small spherical tool dish than the minimum curvature of the workpiece lens curvature. Furthermore, since the arrangement position of the tool plate can be turned around the center of the ball of the tool plate, the setup is easy, and furthermore, the control program can be easily created and the machining cost can be reduced.
[0014]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0015]
FIGS. 1 to 3 show an aspheric lens polishing apparatus using the cam-type spherical core type polishing machine of the present invention, and FIG. 1 is a perspective view in which a part of the aspheric surface polishing machine is cut away. . FIG. 1 shows a processing tool, which is fixedly held by a tool spindle motor 2. The tool spindle motor 2 is fixed to the spindle table 5 and is rotated and held around the processing tool rotation center 15 on the feeding table 6. Further, the feeding table 6 is fixed to a linear guide 7 installed on the swing table 8, and is driven by the tool feeding motor 3 installed on the swing table 8. The ball screw unit 4 driven by the motor 3 controls reciprocation on an axis passing through the swing center of the swing table 8. The cam roller 11 is fixed to the swing table 8 so that 9 / OC = / OC '. A swing motor 14 with a speed reducer 13 is mounted on the swing table 8 coaxially with the cam roller 11, and a swing gear 12 is fixed to an output shaft of the speed reducer 13. The cam roller 11 moves on a cam 10 supported by a die set 9, and a gear pin 16 is arranged on the cam 10 so as to mesh with a swing gear 12. The swing table 8 has a speed reducer 13. The swinging is controlled by the engagement between the swinging gear 12 driven by the swinging motor 14 and the gear pin 16.
[0016]
On the other hand, the lens 20 to be processed is detachably attached to a lens holder 21. The lens holder 21 is supported by a lens rotation motor 24 so as to be rotatable and reciprocable by a spindle sleeve 22 while being rotated. The processing lens 20 is pressed by a spring installed at the tip of the pressing knob 26. Further, the spindle sleeve 22 is fixed to a work 23 upper and lower arm and is moved up and down by a work shaft vertical motor 28. The 23 work upper and lower arm 23 allows the rotation center axis of the lens holder 21 to pass through the swing center of the swing table 8. Is configured.
[0017]
Next, an aspherical surface processing method using the apparatus constituted according to the present invention will be described with reference to FIGS. 4 to 7. First, the lens 20 to be processed is attached to the lens holder 21, and the center of the pseudo spherical surface of the lens 20 to be processed is oscillated. The work vertical motor 28 is controlled and moved so as to be at the center of the moving table 8. The machining tool 1 is attached to the tool spindle motor 2 so that the center axis of the turning of the machining tool 15 and the center of the R of the machining tool 1 are at the same point, and the spindle table 5 is turned and fixed at an arbitrary angle. Further, the swing table 8 is set to an angle at which the swing angle is 0 degree, that is, the line segment / CC ′ connecting the center of the cam roller and the rotation center axis of the lens holder 21 are perpendicular to each other. Further, the tool feeding motor 3 is driven to move the feeding table 6 to bring the lens 20 to be processed into contact with the processing tool 1.
[0018]
Further, the lens holder 21 and the tool spindle motor 2 are rotated, and the computer 40 sends the data of C and θ in FIG. 6 to the control 41 as shown in FIG. The moving table 8 is swung to polish the aspherical lens. At this time, schematic diagrams of an actual trajectory example are as shown in FIGS. 4 and 5, and the correction direction of the difference between the pseudo spherical surface and the processed aspheric surface is the center direction of the swing. Further, the shape of the cam 10 is not an aspherical shape but a spherical surface, and the cam can be replaced with the 10 die set 9 as a reference point. By replacing the cam 10, the trajectory of the processing tool can be drawn from the OR to a plane. It is possible, and in processing, a spherical cam necessary to draw a pseudo spherical surface is attached. Further, on the computer 40, point data can be created by spreadsheet software or the like, and the data can be sequentially transferred to the controller 41 to control more points.
[0019]
Further, the relationship between the pseudo spherical surface and the spherical center of the aspherical lens to be processed will be described. First, in order to achieve the object of the method of the present invention, the spherical center of the pseudo spherical surface of the aspherical lens to be processed and the processing tool The cam is arranged so as to match the oscillating spheres of the robot, and the machining tool is reciprocated at each angle to create an aspheric trajectory. That is, assuming that the angle θ is θ = Tan ⁻¹ (X / Y) and the curvature of the pseudo spherical surface is R, the feeding amount △ is calculated as △ = √ (X ² + Y ² ) −R. By interpolating the angle θ and the feed amount △, an aspheric trajectory is created. Further, the method of the present invention facilitates the manufacture of the tool plate by using a spherical tool plate having a curvature smaller than the minimum curvature of the lens to be processed, and furthermore, has a structure in which the arrangement position of the tool plate can be turned around the spherical center of the tool plate. The setup is easy. According to the apparatus of the present invention, the control program can be easily created, and the processing cost can be reduced.
[0020]
【The invention's effect】
The present invention provides a method of polishing an aspheric lens using a cam-type spherical core type polishing machine constituted by an oscillator that rotates a polishing plate and swings a ball center, wherein the method reciprocates on an axis passing through the center of the oscillator. An aspheric lens polishing method using a cam-type spherical core type polishing machine, characterized in that a possible table and an angle of the oscillating body are interpolated to give an aspheric trajectory control to the polishing dish. A method of polishing an aspheric lens using a cam-type ball-and-center polisher in which the shape of a polishing dish in the method of polishing a spherical lens is a spherical surface having a curvature smaller than the minimum curvature portion of the curvature of the aspheric lens to be processed. An aspheric lens polishing method using a cam-type spherical center type polishing machine that enables a position where the polishing dish is in contact with the aspheric lens to be processed to be rotated as a spherical center of the polishing dish in the lens polishing method, The aspheric lens laboratory An aspherical lens polishing method using the cam-type spherical center grinder for polishing an aspherical surface in the control of the two axes by the use of a cam without the numerical control with three axes or more axes in the method.
[0021]
The present invention also provides a polishing apparatus for an aspheric lens using a cam-type spherical core type polishing machine constituted by an oscillator that rotates a polishing dish and swings a ball center, wherein an axis passing through the center of the oscillator is An aspherical lens polishing apparatus using a cam-type spherical core type polishing machine, comprising: a reciprocating table and a polishing plate for interpolating the angle of the oscillating body, and giving an aspherical trajectory control to the polishing plate. Further, in the above-described aspheric lens polishing apparatus, a spherical core type cam is provided in which a locus of the average curvature of the aspheric lens to be processed is a locus of the tool, and a locus between the curvature of the aspheric lens to be processed and the processing tool is provided. An aspherical lens polishing apparatus using a cam-type ball center polisher having a difference and imparting an aspheric trajectory to the processing tool by extending or retracting the processing tool at each swing angle. It has many effects like:
A. Since the present invention has been developed to solve the conventional disadvantage, the processing tool swings around the spherical center of the pseudo spherical surface with respect to the aspherical shape, and the processing tool has a difference from the pseudo spherical surface. Is corrected in the direction of the spherical center of the pseudo spherical surface, so that aspherical polishing can be performed.
A) According to the method of the present invention, cams are arranged and the processing tool is reciprocated at each angle so that the spherical center of the pseudo spherical surface of the aspherical lens to be processed and the oscillating spherical center of the processing tool coincide with each other. Trajectories can be created. That is, by interpolating the angle θ and the feeding amount △, it is possible to create an aspheric trajectory.
C) According to the method of the present invention, the manufacture of the tool plate can be facilitated by using a spherical tool plate having a curvature smaller than the minimum curvature of the lens to be processed.
D) According to the method of the present invention, the arrangement position of the tool plate has a structure capable of turning around the ball center of the tool plate, so that the setup is easy.
(E) According to the apparatus of the present invention, creation of a control program is facilitated and machining cost is reduced.
According to the apparatus of the present invention, by using a cam, a conventional apparatus which must perform numerical control with three or more axes can perform polishing of an aspheric surface more precisely by controlling two axes. The price of the device can also be provided at a low price.
In addition, the trajectory data of the aspherical surface may be data of two axes, and the program is simplified, and the number of machining steps can be reduced.
[Brief description of the drawings]
FIG. 1 is a cutaway perspective view showing an aspheric lens polishing apparatus according to the present invention.
FIG. 2 is a schematic cutaway perspective view showing a main part of the present invention.
FIG. 3 is a schematic diagram showing a tool setting method according to the present invention.
FIG. 4 is a schematic view showing a concave surface processing method according to the present invention.
FIG. 5 is a schematic view showing a method for processing a convex surface according to the present invention.
FIG. 6 is a schematic explanatory view showing a position data calculation method according to the present invention.
FIG. 7 is a conceptual diagram showing an arrangement of a swinging portion cam roller used in the present invention.
FIG. 8 is an explanatory schematic diagram showing a conventional aspherical surface generating device.
FIG. 9 is an explanatory diagram showing a conventional aspherical surface polishing method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Processing tool 2 Tool spindle motor 3 Tool feeding motor 4 Ball screw unit 5 Spindle table 6 Feeding table 7 Linear guide 8 Swing table 9 Die set 10 Cam 11 Cam roller 12 Swing gear 13 Reducer 14 Swing motor 15 Working tool rotation center Unit 20 Work lens 21 Lens holder 22 Spindle sleeve 23 Work vertical arm 24 Lens rotation motor 25 Timing belt 26 Pressure knob 27 Ball screw 28 Work axis motor 30 Processing tool 31 Lens 40 Computer 41 Controller 42 Tool feeding motor 43 Cam 44 Swing Dynamic motor 101 Frame 102 Tool rotating shaft 103 Tool moving 104 Rotary axis 105 Processing tool (grinding stone)
106 Work axis 107 Work 108 Work axis (rotary axis)
A Tool tilt center B Swing center C Pseudo spherical surface D Difference correction direction E Cam surface R center F Concave cam surface G Convex cam surface H Cam surface R center

Claims (6)

In a method of polishing an aspheric lens using a cam-type spherical polishing machine constituted by an oscillator that rotates a polishing plate and swings a ball center, a table that can reciprocate on an axis passing through the center of the oscillator. An aspherical lens polishing method using a cam-type spherical core type polishing machine, wherein an aspherical trajectory control is given to a polishing plate by interpolating an angle of the oscillator. 2. The aspheric lens using a cam-type spherical core type polishing machine according to claim 1, wherein in the method of polishing an aspheric lens according to the preceding item, the shape of the polishing dish is a spherical surface having a curvature smaller than the minimum curvature portion of the curvature of the aspheric lens to be processed. Polishing method. The method according to claim 1, wherein the position of the polishing dish in contact with the aspherical lens to be processed can be turned as the spherical center of the polishing dish. An aspherical lens polishing method using a core type polishing machine. 4. The method according to claim 1, wherein the aspherical surface is polished by a two-axis control by using a cam instead of a numerical control having three or more axes. An aspherical lens polishing method using a core type polishing machine. In a polishing apparatus for an aspheric lens using a cam-type spherical core polishing machine constituted by an oscillator that rotates a polishing dish and swings a ball center, a table that can reciprocate on an axis passing through the center of the oscillator. An aspheric lens polishing apparatus using a cam-type ball-center type polishing machine, comprising: a polishing plate for interpolating the angle of the oscillating body; and providing an aspheric trajectory control to the polishing plate. 6. The aspheric lens polishing apparatus according to claim 5, further comprising: a spherical centered cam having a locus of an average curvature of the aspheric lens to be processed being a locus of the tool, and a locus between the curvature of the aspheric lens to be processed and the processing tool. 6. An aspherical lens polishing apparatus using a cam type spherical center polishing machine according to claim 5, wherein the processing tool is extended or retracted at each swing angle and an aspheric trajectory is given to the processing tool. .

Images