A turning device and method for off-axis eccentric bi-spherical mirror

Abstract

The application relates to a turning device and method for off-axis eccentric double spherical mirror, wherein the turning device for off-axis eccentric double spherical mirror comprises a fixture tool base, two plugs and multiple pressing pieces; the fixture tool base is used for placing the off-axis eccentric double spherical mirror; the plugs are respectively installed on the narrow edges of the off-axis eccentric double spherical mirror, and are used for limiting the positions of the narrow edges of the off-axis eccentric double spherical mirror; and the pressing pieces are used for fixing the off-axis eccentric double spherical mirror on the fixture tool base. The application can adjust the rotary center axis position by using mechanical positioning, so that the machining is simplified; the machining efficiency is improved, and the surface shape precision and surface roughness of the curved surface are ensured.

Description

Technical Field

[0001] This application relates to the field of optical ultra-precision machining technology, and in particular to an off-axis eccentric double spherical mirror turning apparatus and method. Background Technology

[0002] A double spherical mirror is an unconventional three-dimensional surface formed by rotating and compressing two circles of equal radius around a central axis spaced a certain distance apart. Due to its unique optical properties, it is used in fields such as lasers and optical imaging. Currently, the ultra-precision machining of double spherical mirrors in China is mainly accomplished by milling or three-axis linkage. However, milling results in high surface accuracy and roughness, while three-axis linkage machining leads to poor rotational symmetry of individual spherical surfaces, making it difficult to meet the requirements of reflective optical systems.

[0003] Therefore, the inventors have provided an off-axis eccentric double spherical mirror turning apparatus and method. Summary of the Invention

[0004] (1) Technical problems to be solved

[0005] This application provides an off-axis eccentric double spherical mirror turning apparatus and method. The technical problem to be solved is that the milling process has high surface accuracy and surface roughness, and the three-axis linkage machining will result in poor rotational symmetry of a single spherical surface, which makes it difficult to meet the requirements of the reflective optical system.

[0006] (2) Technical solution

[0007] In a first aspect, this application provides a turning apparatus for an off-axis eccentric double spherical mirror, including a fixture base, two blocking blocks, and multiple pressure plates; the fixture base is used to place the off-axis eccentric double spherical mirror, the blocking blocks are respectively installed on the narrow sides of the off-axis eccentric double spherical mirror to limit the position of the narrow sides of the off-axis eccentric double spherical mirror; the pressure plates are used to fix the off-axis eccentric double spherical mirror on the fixture base.

[0008] Furthermore, the fixture base includes a groove bottom surface, a first plane, and a second plane; the groove bottom surface is used to contact the bottom surface of the off-axis eccentric double spherical mirror; the first plane and the second plane are used to limit the position of the long side of the off-axis eccentric double spherical mirror.

[0009] Furthermore, the fixture base also includes a third plane; the third plane is used to contact the lathe vacuum chuck.

[0010] Furthermore, the fixture base also includes multiple first threaded holes and tool retraction holes; the first threaded holes are used to position and install the plug; the tool retraction holes are used to perform milling finishing on the plug.

[0011] Furthermore, the fixture base also includes a plurality of second threaded holes; the second threaded holes are used to position and install the pressure plate.

[0012] Furthermore, the plug includes a countersunk hole, a fourth plane, and a allowance groove; the countersunk hole is used to fix the position of the plug; the fourth plane is used to limit the narrow side position of the off-axis eccentric double spherical mirror; the allowance groove is used to achieve milling finishing of the fourth plane.

[0013] Furthermore, the tablet includes a chamfered hole; the chamfered hole is used to fix the position of the tablet.

[0014] Secondly, this application provides a method for turning an off-axis eccentric double spherical mirror, applied to the off-axis eccentric double spherical mirror turning apparatus described above, comprising:

[0015] During the cutting process, the bottom surface of the off-axis eccentric double spherical mirror is placed on the bottom surface of the groove of the fixture base;

[0016] The two long sides of the off-axis eccentric double spherical mirror are respectively attached to the first plane and the second plane of the fixture base;

[0017] When machining the left hemisphere, the narrow side of the off-axis eccentric double spherical mirror away from the left hemisphere is fitted with the fourth plane of the block.

[0018] When machining the right hemisphere, the narrow side of the off-axis eccentric double spherical mirror away from the right hemisphere is fitted with the fourth plane of the block.

[0019] The off-axis eccentric double spherical mirror is fixed on the fixture base by pressing a plate, and the third plane of the off-axis eccentric double spherical mirror is engaged with the lathe vacuum chuck.

[0020] Furthermore, when machining the left hemisphere, the rotation center of the left hemisphere coincides with the rotation center of the machine tool spindle; when machining the right hemisphere, the rotation center of the right hemisphere coincides with the rotation center of the machine tool spindle.

[0021] Furthermore, the fixture base is cylindrical in shape, and the rotation axis of the fixture base is aligned with the rotation axis of the lathe spindle by adjusting the runout of the outer circle of the cylinder using a dial indicator.

[0022] (3) Beneficial effects

[0023] The above-mentioned technical solution of this application has the following advantages:

[0024] The off-axis eccentric double spherical mirror turning apparatus provided in the first aspect of this application has a compact overall structure. It uses mechanical positioning to adjust the position of its rotation center axis, which simplifies the machining process. While improving machining efficiency, it ensures the surface accuracy and surface roughness of the curved surface, and has great application potential in optical ultra-precision turning.

[0025] It is understandable that the beneficial effects of the second aspect mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1 A schematic diagram of the off-axis eccentric double spherical mirror turning apparatus provided in this application;

[0028] Figure 2 This is a structural schematic diagram of the fixture base provided in this application;

[0029] Figure 3 This is a schematic diagram of the block structure provided in this application;

[0030] Figure 4 This is a schematic diagram of the off-axis eccentric double spherical mirror provided in this application.

[0031] Reference numerals: 10, Fixture base; 101, Groove bottom surface; 102, First plane; 103, Third plane; 104, First threaded hole; 105, Relief hole; 106, Second threaded hole; 107, Second plane; 20, Block; 201, Countersunk through hole; 202, Fourth plane; 203, Allowance groove; 30, Pressure plate; 301, Chamfered hole; 40, Off-axis eccentric double spherical mirror; 401, Left hemisphere; 402, Right hemisphere; 403, First long side plane; 404, Second long side plane; 405, Spherical extrusion line; 406, Mirror bottom surface. Detailed Implementation

[0032] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of this application with unnecessary detail.

[0033] It should be understood that, when used in this application specification and appended claims, the term "comprising" indicates the presence of the described feature, integral, step, operation, element, and / or component, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof. The terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application 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 of this application. Furthermore, in the description of this application specification and appended claims, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0034] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized.

[0035] A double spherical mirror is an unconventional three-dimensional surface formed by rotating and compressing two circles of equal radius around a central axis spaced a certain distance apart. Due to its unique optical properties, it is used in fields such as lasers and optical imaging. Currently, the ultra-precision machining of double spherical mirrors in China is mainly accomplished by milling or three-axis linkage. However, milling results in high surface accuracy and roughness, while three-axis linkage machining leads to poor rotational symmetry of individual spherical surfaces, making it difficult to meet the requirements of reflective optical systems.

[0036] The off-axis eccentric double spherical reflector addressed in this application is formed by the mutual compression of two spherical surfaces with very close central axes, and no related patent has proposed a processing solution.

[0037] To achieve an ultra-precision turning process for an off-axis eccentric double spherical reflector, this application provides a machining device and machining method with high positioning accuracy and simple installation based on the characteristics of off-axis eccentric double spherical reflectors.

[0038] The specific embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this application, but are not intended to limit the scope of this application.

[0039] The off-axis eccentric double spherical mirror turning apparatus provided in this embodiment includes a fixture base, two blocking blocks, and multiple pressure plates. The fixture base is used to place the off-axis eccentric double spherical mirror. The blocking blocks are respectively installed on the narrow sides of the off-axis eccentric double spherical mirror to limit the position of the narrow sides of the off-axis eccentric double spherical mirror. The pressure plates are used to fix the off-axis eccentric double spherical mirror on the fixture base.

[0040] In some embodiments, the fixture base includes a groove bottom surface, a first plane, and a second plane; the groove bottom surface is used to contact the bottom surface of the off-axis eccentric double spherical mirror; the first plane and the second plane are used to limit the position of the long side of the off-axis eccentric double spherical mirror.

[0041] In some embodiments, the fixture base further includes a third plane; the third plane is used to contact the lathe vacuum chuck.

[0042] In some embodiments, the fixture base further includes a plurality of first threaded holes and a tool retraction hole; the first threaded holes are used to position and install the plug; the tool retraction hole is used to perform milling finishing on the plug.

[0043] In some embodiments, the fixture base further includes a plurality of second threaded holes; the second threaded holes are used to position and install the pressure plate.

[0044] In some embodiments, the plug includes a countersunk hole, a fourth plane, and a allowance groove; the countersunk hole is used to fix the position of the plug; the fourth plane is used to limit the narrow edge position of the off-axis eccentric double spherical mirror; and the allowance groove is used to achieve milling finishing of the fourth plane.

[0045] In some embodiments, the pressure plate includes a chamfered hole; the chamfered hole is used to fix the position of the pressure plate.

[0046] like Figures 1 to 3As shown, in application, the processing device includes an off-axis eccentric double spherical mirror fixture base 10, a blocking block 20 for fixing the position of the double spherical mirror, and a pressure plate 30 with a suitable height. The fixture base 10 includes four key planes: a groove bottom surface 101 that contacts the bottom surface 406 of the mirror; two planes that limit the position of the long side of the mirror, namely the first plane 102 and the second plane 107; a bottom surface that contacts the lathe vacuum chuck, namely the third plane 103; four first threaded holes 104 for positioning and installing the blocking block; a relief hole 105 left after milling and finishing the blocking block; and four second threaded holes 106 for positioning and installing the pressure plate. The blocking block 20 for fixing the position of the double spherical mirror mainly includes a countersunk through hole 201 for fixing the position of the blocking block; a plane that limits the position of the narrow side of the mirror, namely the fourth plane 202; and a allowance groove 203 left after milling and finishing the fourth plane 202. The allowance groove avoids damage to the ground groove bottom surface during milling. The tablet 30 has a chamfered hole 301.

[0047] The overall manufacturing process of the processing device is as follows: The blanks of the forming fixture base 10, the blocking block 20, and the pressure plate 30 are machined, requiring a 1mm allowance for the four planes 102, 107, and 202 of the positioning reflector; Threaded holes 104 and 106 and a relief hole 105 are drilled on the fixture base 10 according to the drawings; a countersunk through hole 201 is drilled on the blocking block 20; and a chamfered hole 301 is drilled on the pressure plate 30; the first plane 102, which restricts the long side position of the reflector, is milled and finished; the bottom surface 101 of the groove that contacts the bottom surface 406 of the reflector is ground; and the third plane 103, which contacts the lathe vacuum chuck, is ground; the two blocking blocks 20 are installed and fixed on the fixture base 10 using hexagonal screws; and the fourth plane 202, which restricts the narrow side position of the reflector, is milled and finished.

[0048] like Figure 4 As shown, the off-axis eccentric double spherical mirror 40 mainly includes a left hemisphere 401, a right hemisphere 402, and two long-side planes 403 and 404. The two spherical surfaces are obtained by rotating two circles of equal diameter around the rotation axes of the left and right hemispheres by 360° respectively. The spherical extrusion line 405 is formed by the mutual extrusion of the two spherical surfaces. Δ x represents the deviation of the left hemisphere rotation axis from the workpiece center in the X direction. Δ y represents the deviation of the left hemisphere rotation axis from the workpiece center in the Y direction.

[0049] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application.

[0050] This embodiment also provides a method for turning an off-axis eccentric double spherical mirror, applied to the off-axis eccentric double spherical mirror turning apparatus described above, including:

[0051] During the cutting process, the bottom surface of the off-axis eccentric double spherical mirror is placed on the bottom surface of the groove of the fixture base;

[0052] The two long sides of the off-axis eccentric double spherical mirror are respectively attached to the first plane and the second plane of the fixture base;

[0053] When machining the left hemisphere, the narrow side of the off-axis eccentric double spherical mirror away from the left hemisphere is fitted with the fourth plane of the block.

[0054] When machining the right hemisphere, the narrow side of the off-axis eccentric double spherical mirror away from the right hemisphere is fitted with the fourth plane of the block.

[0055] The off-axis eccentric double spherical mirror is fixed on the fixture base by pressing a plate, and the third plane of the off-axis eccentric double spherical mirror is engaged with the lathe vacuum chuck.

[0056] In some embodiments, when machining the left hemisphere, the rotation center of the left hemisphere coincides with the rotation center of the machine tool spindle; when machining the right hemisphere, the rotation center of the right hemisphere coincides with the rotation center of the machine tool spindle.

[0057] In some embodiments, the fixture base is cylindrical in shape, and the rotation axis of the fixture base is made to coincide with the rotation axis of the lathe spindle by adjusting the runout of the outer circle of the cylinder with a dial indicator.

[0058] In application, during machining, the off-axis eccentric double spherical mirror 40 is placed on the fixture base 10. The first long side plane 403 of the mirror is aligned with the second plane 107 that restricts the position of the long side of the mirror, and the second long side plane 404 of the mirror is aligned with the first plane 102 that restricts the position of the long side of the mirror. When machining the left hemisphere, the narrow side plane of the mirror is aligned with the fourth plane 202 that restricts the position of the narrow side of the mirror by the right block. At this time, the rotation center of the left hemisphere is aligned with the rotation center of the machine tool spindle. When machining the right hemisphere, the narrow side plane of the reflector is aligned with the fourth plane 202, which restricts the position of the narrow side of the reflector by the left block. At this time, the rotation center of the right hemisphere coincides with the rotation center of the machine tool spindle. The reflector 40 is pressed firmly with the pressure plate 30 until it cannot move. The bottom surface of the fixture, i.e., the third plane 103, is matched with the vacuum chuck of the lathe. The fixture base 10 is cylindrical in shape. The rotation axis of the fixture base 10 is aligned with the rotation axis of the lathe spindle by adjusting the runout of the outer circle of the cylinder with a dial indicator.

[0059] The off-axis eccentric double-spherical mirror turning apparatus and method provided in this application embodiment uses a set of high-precision mechanical tooling to align the rotation center axis of the double spherical mirror with the rotation center axis of the spindle of an ultra-precision turning machine tool. A clamping plate is used to fix the mirror body, and the machining of the two spherical surfaces is completed using a rotary cutting C-axis mode. This application can achieve ultra-precision turning of off-axis eccentric double spherical mirrors, ensuring both the surface shape accuracy and surface roughness of the off-axis eccentric double-spherical mirror while maintaining the rotational symmetry of each individual spherical surface. It simplifies three-axis linkage machining into rotary machining where the workpiece and the machine tool's rotation center axis coincide, transforming off-axis machining into coaxial machining. This machining apparatus is simple, has excellent adjustment and positioning accuracy, low manufacturing cost, and high machining efficiency.

[0060] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0061] Those skilled in the art will recognize that the device and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0062] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for machining an off-axis eccentric double spherical mirror, characterized in that, An apparatus for machining an off-axis eccentric double spherical mirror is provided. The apparatus includes a fixture base, two blocking blocks, and multiple pressure plates. The fixture base is used to place the off-axis eccentric double spherical mirror. The blocking blocks are respectively installed on the narrow sides of the off-axis eccentric double spherical mirror to limit the position of the narrow sides of the mirror. The pressure plates are used to fix the off-axis eccentric double spherical mirror on the fixture base. The fixture base includes a groove bottom surface, a first plane, and a second plane; the groove bottom surface is used to contact the bottom surface of the off-axis eccentric double spherical mirror. The first plane and the second plane are used to limit the position of the long side of the off-axis eccentric double spherical mirror; the fixture base also includes a third plane; the third plane is used to contact the lathe vacuum chuck; the blocking block includes a fourth plane; the fourth plane is used to limit the position of the narrow side of the off-axis eccentric double spherical mirror; The method includes: During the cutting process, the bottom surface of the off-axis eccentric double spherical mirror is placed on the bottom surface of the groove of the fixture base; The two long sides of the off-axis eccentric double spherical mirror are respectively attached to the first plane and the second plane of the fixture base; When machining the left hemisphere, the narrow side of the off-axis eccentric double spherical mirror away from the left hemisphere is fitted with the fourth plane of the block. When machining the right hemisphere, the narrow side of the off-axis eccentric double spherical mirror away from the right hemisphere is fitted with the fourth plane of the block. The off-axis eccentric double spherical mirror is fixed on the fixture base by pressing a plate, and the third plane of the off-axis eccentric double spherical mirror is engaged with the lathe vacuum chuck.

2. The off-axis eccentric double spherical mirror turning method as described in claim 1, characterized in that, The fixture base also includes multiple first threaded holes and tool retraction holes; the first threaded holes are used to position and install the plug; the tool retraction holes are used to perform milling finishing on the plug.

3. The off-axis eccentric double spherical mirror turning method as described in claim 1, characterized in that, The fixture base also includes multiple second threaded holes; the second threaded holes are used to position and install the pressure plate.

4. The off-axis eccentric double spherical mirror turning method as described in claim 1, characterized in that, The block includes a countersunk hole and a allowance groove; the countersunk hole is used to fix the position of the block; the allowance groove is used to achieve milling finishing of the fourth plane.

5. The off-axis eccentric double spherical mirror turning method as described in claim 1, characterized in that, The pressure plate includes a chamfered hole; the chamfered hole is used to fix the position of the pressure plate.

6. The off-axis eccentric double spherical mirror turning method as described in claim 1, characterized in that, When machining the left hemisphere, the rotation center of the left hemisphere coincides with the rotation center of the machine tool spindle; when machining the right hemisphere, the rotation center of the right hemisphere coincides with the rotation center of the machine tool spindle.

7. The off-axis eccentric double spherical mirror turning method as described in claim 1, characterized in that, The fixture base is cylindrical in shape. The rotation axis of the fixture base is aligned with the rotation axis of the lathe spindle by adjusting the runout of the outer circle of the cylinder using a dial indicator.

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