CN103487911A - Precision positioning and adjusting device for off-axis optical element - Google Patents

Abstract

The invention belongs to the technical field of off-axis optical devices, in particular to an off-axis optical element precision positioning adjustment device. The adjustment device is composed of off-axis optical elements, locking screws, spring steel sheets, adjustment bases, adjustment screws, and fixing screws; The shape of the element is matched; the off-axis optical element and the spring steel sheet are fixed by the fixing screw; the adjustment base and the spring steel sheet are fixed by the locking screw; the pitch angle of the off-axis optical element can be realized by adjusting the adjustment amount of the two adjustment screws of the base and adjustment of the deflection angle. The invention has the advantages of simple structure, low cost, high sensitivity and good stability, and is applicable to the angle adjustment of off-axis optical elements, and also applicable to the angle adjustment of other coaxial optical elements, self-adaptive mirrors, CCD imaging components and other optical elements.

Description

Off-axis optical element precision positioning adjustment device

technical field

The invention belongs to the technical field of off-axis optical devices, and in particular relates to a device capable of adjusting and positioning the angle and orientation of off-axis optical elements in an optical system.

Background technique

Off-axis optical element is an extremely important optical device, which includes planar optical element, free-form surface element, off-axis aspheric optical element, functional structured optical surface, optical prism, and has a wide range of applications in the field of imaging optics and illumination optics. application. With the increasing level of processing and inspection of off-axis optical components, more and more optical instruments are designed with off-axis optical components. It mainly has the advantages of compact structure, good imaging quality, wide spectrum and light weight. The optical system using off-axis optical elements can correct aberrations, improve imaging quality, and achieve special imaging effects. For example, after using off-axis optical elements in ultra-thin projectors, the throw ratio can be reduced to less than 0.2, which can realize ultra-short distance projection of large imaging frames; for example, using off-axis parabolic mirrors in collimators can achieve Collimate light of different wavelengths without focusing; for example, in an off-axis three-mirror telescope optical system, the use of off-axis optical elements can achieve high-resolution, large field of view, long focal length, and wide-spectrum imaging requirements, and there is no Block in the middle. For example, the use of off-axis illumination in the lithography machine can improve the uniform illuminance of light, thereby improving the resolution of the lithography machine. Among them, a large number of off-axis optical elements are used in the illumination system and projection imaging system of the EUV lithography machine.

The assembly and adjustment of optical components should ensure that the optical components are within a given tolerance range, and optical components with low tolerance requirements can ensure their assembly accuracy through tolerance matching. For optical elements with high tolerance requirements, an adjustment device is required to adjust them to ensure that the optical elements are within a reasonable tolerance range. Since the influence of the azimuth angle error of the off-axis optical element is greater than that of the coaxial system, the assembly accuracy of the off-axis optical element is higher than that of the coaxial system. The commonly used adjustment method is to use a complex angle adjustment mechanism, such as a two-dimensional angle adjustment table, a three-dimensional angle adjustment table, etc., which have complex structures, large volume, high cost, poor stability, and low sensitivity. Axis optics are fixed.

The adjustment of the off-axis optical element is divided into two steps, that is, position adjustment and angle adjustment. Position adjustment is to ensure that the front and rear orientations of the off-axis optical components, and the left and right orientations are within the range given by the tolerance. Angular adjustment is to ensure that the yaw and pitch of the off-axis optics are within a given tolerance range. The purpose of position adjustment and angle adjustment is to realize that the optical axis of the off-axis optical element and the optical axis of the optical system are within a given tolerance range, and the relative position with other optical elements is also within a given tolerance range. The position adjustment is a preliminary adjustment, and the position adjustment and fixation of the off-axis optical elements can be easily realized by using conventional methods. The angle adjustment belongs to fine adjustment. The angle adjustment device is generally composed of a support frame, an adjustment base, a reflector frame, a connecting spring, a support ball, and an adjustment screw. The adjustment base and the reflector frame are supported by a support ball and fixed by a connection spring. , adjusted by means of an adjusting screw near the connecting spring. Although this structure can realize the angle adjustment of off-axis optical elements, it is difficult to effectively fix the off-axis optical elements by using springs for connection, resulting in low reliability; at the same time, there are complex structures, many parts, large sizes, and high costs. question. This requires us to design a new adjustment and fixing device so that it can fix off-axis optical elements while completing the adjustment task.

Contents of the invention

The object of the present invention is to provide an adjustment device with simple structure, low cost, high sensitivity and good stability, which can adjust the angle of off-axis optical elements and fix the off-axis optical elements at the same time.

The adjustment device provided by the present invention has a structure as shown in Figure 1, and is composed of an off-axis optical element 1, a locking screw 2, a spring steel sheet 3, an adjustment base 4, an adjustment screw 5, and a fixing screw 6; the spring steel sheet 3. The overall shape is convex, with windows on both sides of the lower part; the overall shape matches the shape of the off-axis optical element 1; there are locking screw holes on both sides of the head of the spring steel sheet 3, and fixed screw holes on the four corners of the lower part; The off-axis optical element 1 and the spring steel sheet 3 are fixed by the fixing screw 6 through the fixing screw hole; the adjustment base 4 and the spring steel sheet 3 are fixed by the locking screw 2 through the locking screw hole; the adjustment base 4 The lower part is provided with 2 adjusting screw holes, and the 2 adjusting screws 5 pass through the adjusting screw holes to contact with the lower part of the spring steel sheet 3, and the spring steel sheet 3 is elastically deformed by adjusting the adjustment amount of the adjusting screw 5, thereby realizing the tilt angle (including pitching). Angle and deflection angle), at the same time, the elastic force generated by the elastic deformation of the spring steel sheet 3 fixes the adjusted off-axis optical element 1 and the spring steel sheet 3 on the adjustment base 4 .

In the present invention, the angle adjustment amount of the spring steel sheet 3 can be set as required. In one embodiment, the angle adjustment amount of the spring steel sheet 3 is ±2.5 degrees.

In the present invention, the adjustment amount of the adjusting screw 5 can be set as required, for example, the adjustment amount can be set to 3-6 mm. In one embodiment, the adjustment amount of the adjusting screw 5 is 5mm, which can realize the adjustment of the pitch ±2.5 degrees and the yaw ±2.5 degrees of the off-axis optical element.

The adjustment device of the present invention uses a spring steel sheet to replace the original adjustment mechanism composed of a connecting spring, a support ball, and a precision adjustment screw, and realizes angle adjustment through elastic deformation of the spring steel sheet, thereby simplifying the structure of the adjustment device. The adjustment device can also play a fixed role while completing the adjustment, and has high adjustment sensitivity, high precision and good stability.

The adjustment device of the invention can realize miniaturization and lighten the weight of the mechanism, so as to be suitable for the adjustment of off-axis optical elements of different sizes.

The adjusting device of the present invention is simple in structure, easy to adjust, and convenient to use.

The spring steel sheet of the adjusting device of the present invention adopts common materials, and has low cost and is easy to manufacture.

The adjustment device of the present invention is not only suitable for angle adjustment of off-axis optical elements, but also for angle adjustment of other coaxial optical elements, adaptive mirrors, CCD imaging components and other optical elements, and can also be widely used in other adjustment fields.

Description of drawings

Figure 1 is a structural diagram of the adjustment device.

Figure 2 is a cross-sectional view of the adjustment device.

Figure 3 is a schematic diagram of the spring steel sheet structure.

Numbers in the figure: 1 is an off-axis optical element, 2 is a locking screw, 3 is a spring steel sheet, 4 is an adjustment base, 5 is an adjustment screw, and 6 is a fixing screw.

Detailed ways

As shown in Figure 1, the adjustment device consists of an off-axis optical element 1, a locking screw 2, a spring steel sheet 3, an adjustment base 4, an adjustment screw 5, and a fixing screw 6.

As shown in FIG. 1 , the off-axis optical element 1 and the spring steel sheet 3 of the adjustment device are fixed by fixing screws 6 . In this implementation case, the locking screw is M4×8mm.

As shown in FIG. 2 , the adjustment base 4 and the spring steel sheet 3 of the adjustment device are fixed by locking screws 2 . In this implementation case, the locking screw is M4×6mm.

As shown in Figure 3, there are 6 connecting holes on the spring steel sheet 3, and the fixing screw 6 can fix the off-axis optical element 1 and the spring steel sheet 3 through the lower 4 connecting holes, and the fixing screw 2 passes through the upper 2 connecting holes The adjustment base 4 and the spring steel sheet 3 can be fixed. The material of the spring steel sheet can be high-quality carbon structural steel, carbon tool steel, high-speed tool steel, and stainless steel. The material of the spring steel sheets in this implementation case is carbon structural steel.

As shown in FIG. 2 , a certain amount of elastic deformation should be reserved during manufacture of the spring steel sheet to facilitate adjustment by the adjusting screw 5 . The thickness of the spring steel sheet in this implementation is 4mm, the elastic deformation is 3mm, and the angle adjustment is ±2.5°.

As shown in FIG. 2 , the adjustment device makes the elastic deformation of the spring steel sheet 3 through the change of the adjustment amount of the adjustment screw 5 , and then realizes the adjustment of the inclination angle. In this example, there are two adjustment screws 5, and the adjustment amount of the adjustment screws 5 is 5mm, which can realize the adjustment of the pitch ±2.5° and the yaw ±2.5° of the off-axis optical element.

Claims (3)

1. An off-axis optical element precision positioning adjustment device is characterized in that it is composed of an off-axis optical element, a locking screw, a spring steel sheet, an adjustment base, an adjustment screw, and a fixing screw; the spring steel sheet is in a convex shape as a whole, There are windows on both sides of the lower part; the overall shape matches the shape of the off-axis optical element; locking screw holes are opened on both sides of the head of the spring steel sheet, and fixed screw holes are opened on the four corners of the lower part; the off-axis optical element and the spring The steel sheet is fixed by the fixing screw through the fixing screw hole; the adjustment base and the spring steel sheet are fixed by the locking screw through the locking screw hole; the lower part of the adjustment base is provided with 2 adjustment screw holes, and the 2 adjustment screws pass through The adjustment screw hole is in contact with the lower part of the spring steel sheet, and the spring steel sheet is elastically deformed by the adjustment amount of the adjustment screw, thereby realizing the adjustment of the inclination angle. At the same time, the elastic force generated by the elastic deformation of the spring steel sheet makes the adjusted off-axis The optics and spring steel are fixed on the adjustment base. 2. The off-axis optical element precision positioning adjustment device according to claim 1, characterized in that the angle adjustment amount of the spring steel sheet is ±2.5 degrees. 3. The off-axis optical element precision positioning adjustment device according to claim 1, characterized in that the adjustment amount of the adjustment screw is 3-6 mm, so as to realize the adjustment of the off-axis optical element pitch ± 2.5 degrees and yaw ± 2.5 degrees.

Images