Adjusting method and adjusting device

Abstract

Provided are an adjusting method and an adjusting device with which preparation of a replacement lens and lens barrel is unnecessary. The adjusting method includes a first step (S1) for measuring an initial aberration, which is a transmitted wavefront aberration, of a lens group accommodated in a lens barrel, a second step (S2) for measuring a plurality of transmitted wavefront aberrations by moving the lenses constituting the lens group, a third step (S3) for calculating a sensitivity of the lenses constituting the lens group, on the basis of an amount of change, a fourth step (S4) for calculating an amount of movement of the lenses constituting the lens group, on the basis of the sensitivity, a fifth step (S5) for moving the lenses constituting the lens group, and a sixth step (S6) for evaluating the lens group of which the lenses have been moved, wherein, if it is determined from the result of the evaluation that an adjustment termination condition is not satisfied, the second step to the sixth step are repeated without replacing the lenses constituting the lens group and the lens barrel.

Description

Adjustment method and adjustment device CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to Japanese Patent Application No. 2021-107127 (filed June 28, 2021), the entire disclosure of which is incorporated herein by reference.

[0002] The present disclosure relates to a regulation method and a regulation device.

[0003] An optical system is composed of one or more lenses, and various errors can occur during assembly. To reduce these errors, a method is known in which the wavefront aberration of the optical system is measured and the position of each lens in the optical system is adjusted to reduce the wavefront aberration. For example, Patent Document 1 discloses a measurement method in which the adjustment amount of the optical system to be tested is calculated based on the measured transmitted wavefront and the sensitivity of each aberration component.

[0004] Japanese Patent Application Laid-Open No. 2019-191121

[0005] An adjustment method according to an embodiment of the present disclosure includes: a first step of measuring initial aberration, which is transmitted wavefront aberration of a lens group housed in a lens barrel; a second step of measuring a plurality of transmitted wavefront aberrations by moving lenses constituting the lens group in at least one direction selected from the optical axis direction and a direction perpendicular to the optical axis direction; a third step of calculating sensitivity of the lenses constituting the lens group based on changes in the measured plurality of transmitted wavefront aberrations from the initial aberration; a fourth step of calculating movement amounts of the lenses constituting the lens group based on the calculated sensitivities; a fifth step of moving the lenses constituting the lens group based on the calculated movement amounts; and a sixth step of evaluating the lens group whose lenses have moved based on the calculated movement amounts, and when it is determined from the result of the evaluation that the adjustment termination condition is not satisfied, the second step to the sixth step are performed again without replacing the lenses constituting the lens group and the lens barrel.

[0006] an adjusting device according to an embodiment of the present disclosure, the adjusting device comprising: an incident optical system that causes light emitted from a light source to be incident on a lens group housed in a lens barrel; a light receiving system that receives light that has passed through the lens group; a wavefront sensor that receives light via the light receiving system; a driver that moves lenses that constitute the lens group; and a controller, wherein the controller performs: a first process of calculating an initial aberration that is a transmitted wavefront aberration of the lens group based on information from the wavefront sensor; a second process of causing the driver to move the lenses that constitute the lens group in at least one direction selected from the optical axis direction and a direction orthogonal to the optical axis direction, and calculating a plurality of transmitted wavefront aberrations based on information from the wavefront sensor; a third process of calculating sensitivities of the lenses that constitute the lens group based on changes in the calculated plurality of transmitted wavefront aberrations from the initial aberration; a fourth process of calculating movement amounts of the lenses that constitute the lens group based on the calculated sensitivities; and a fifth process of causing the driver to move the lenses that constitute the lens group based on the calculated movement amounts. and a sixth process of evaluating the lens group whose lenses have moved based on the calculated movement amount, and if it is determined from the results of the evaluation that the adjustment termination condition is not satisfied, the second process to the sixth process are performed again without replacing the lenses and the lens barrel that constitute the lens group.

[0007] FIG. 1 is a diagram illustrating a configuration example of an adjustment device according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view illustrating adjustment parameters for a lens group. FIG. 3 is a diagram illustrating a lens group and a drive unit. FIG. 4 is a cross-sectional view illustrating a lens group and a drive unit. FIG. 5 is a diagram illustrating a method for obtaining an optimal solution. FIG. 6 is a diagram illustrating an example in which an optimal solution cannot be obtained. FIG. 7 is a flowchart illustrating an adjustment method according to an embodiment of the present disclosure. FIG. 8 is a diagram illustrating another configuration example of an adjustment device according to an embodiment of the present disclosure. FIG. 9 is a diagram illustrating another configuration example of an adjustment device according to an embodiment of the present disclosure. FIG. 10 is a diagram illustrating another configuration example of an adjustment device according to an embodiment of the present disclosure.

[0008] Hereinafter, an adjustment method and an adjustment device according to an embodiment of the present disclosure will be described with reference to the drawings.

[0009] 1 is a diagram showing an example of the configuration of an adjustment device according to this embodiment. The adjustment device is a device that automatically adjusts lenses that make up a lens group 10 housed in a lens barrel so that the lens group 10 can achieve desired optical performance. In this embodiment, the lens group 10 is a lens assembly that is manufactured as a product. The adjustment device is used in the manufacturing process of the lens assembly.

[0010] The adjustment device includes an incident optical system 2 , a light receiving system 3 , a wavefront sensor 4 , a drive unit 5 , and a control unit 6 .

[0011] The incident optical system 2 causes light emitted by the light source 1 to be incident on the lens group 10. The incident optical system 2 may be, for example, a convex lens, but is not limited to this. The light source 1 may be, for example, a laser diode (LD), but is not limited to this.

[0012] The light receiving system 3 receives the light that has passed through the lens group 10. The light receiving system 3 may be, for example, a convex lens, but is not limited to this.

[0013] The wavefront sensor 4 receives light via the light-receiving system 3 and measures the aberration of the wavefront of the light. The wavefront sensor 4 may be, for example, a Shack-Hartmann sensor, but is not limited to this. The wavefront sensor 4 outputs information including data on the detected aberration to the control unit 6.

[0014] The driving unit 5 moves the lenses constituting the lens group 10 and adjusts the lenses so as to reduce the transmitted wavefront aberration of the lens group 10. The driving unit 5 may be configured to include an electric manipulator as described below. The driving unit 5 may also be configured to include a driving mechanism such as a motor that rotates a screw that adjusts the spacing between the lenses.

[0015] The control unit 6 controls the operation of the adjustment device and performs various calculations required for the operation of the adjustment device. The control unit 6 may be, for example, a computer, but is not limited to this. The control unit 6 calculates the transmitted wavefront aberration of the lens group 10 based on information from the wavefront sensor 4. The control unit 6 causes the drive unit 5 to move the lenses constituting the lens group 10. The control unit 6 calculates the sensitivity of the lenses. The control unit 6 calculates the amount of movement of the lenses. The control unit 6 also evaluates the optical performance of the lens group 10. The evaluation of the lens group 10 may be performed by determining whether the transmitted wavefront aberration of the lens group 10 has reached a target value, for example, using an evaluation function described below. As another example, the evaluation of the lens group 10 may be performed based on optical performance such as MTF (Modulation Transfer Function).

[0016] FIG. 2 is a cross-sectional view illustrating adjustment parameters for the lens group 10. In FIG. 2, Cartesian coordinates corresponding to the orientation of the lens group 10 are set. The z-axis direction is a direction parallel to the optical axis L of the lens 11-1, which is located closest to the object (closest to the light source 1) among the multiple lenses 11 that make up the lens group 10. The positive z-axis direction may be expressed as the forward direction. The negative z-axis direction may be expressed as the image side or rearward direction. The x-axis direction corresponds to the width direction of the lens group 10. The y-axis direction corresponds to the depth direction of the lens group 10.

[0017] The lens group 10 includes a plurality of lenses 11. When distinguishing between the lenses 11, they may be referred to as lens 11-1, lens 11-2, ..., lens 11-N (N is an integer of 2 or more) in order from the front to the rear. In the following, the lens group 10 will be described taking as an example a case where N is 3, but N may be 2 or 4 or more. The lens group 10 shown in FIG. 2 has an adjustment parameter x １ , x ２ , x ３ , x ４ x １ is the air gap between the lens 11-1 and the lens 11-2. ２ is the air gap between the lens 11-2 and the lens 11-3. ３ is the amount of eccentricity between the lens 11-1 and the lens 11-2.４ is the amount of decentering between the lens 11-1 and the lens 11-3.

[0018] Each of the multiple lenses 11 that make up the lens group 10 is housed in a lens barrel. As shown in FIG. 2, the lens barrel 12 of the lens 11-1 and the lens barrel 12 of the lens 11-2 are connected by a screw 14 with a spacer 13 sandwiched between them. Similarly, the lens barrel 12 of the lens 11-2 and the lens barrel 12 of the lens 11-3 are connected by a screw 14 at a position not shown in FIG. 2 with a spacer 13 sandwiched between them. The screw 14 is turned and tightened by the drive unit 5. Therefore, x １ and x ２ is adjusted by rotating the screw using the driving unit 5. In other words, the driving unit 5 can move the lens 11 that constitutes the lens group 10 in the optical axis direction.

[0019] 3 and 4 are diagrams for explaining the lens group 10 and the drive unit 5. The Cartesian coordinates and symbols shown in FIGS. 3 and 4 are the same as those in FIG. 2. The electric manipulator of the drive unit 5 holds the lens barrel 12 of the lens group 10. FIG. 3 is a view of the lens group 10 as seen from the object side. FIG. 4 is a cross-sectional view similar to FIG. 2. The electric manipulator of the drive unit 5 can move each of the lens barrels 12 that house the lenses 11 in directions within the xy plane. Therefore, x ３ and x ４ is adjusted by the driving unit 5. In other words, the driving unit 5 can move the lenses 11 that constitute the lens group 10 in a direction perpendicular to the optical axis direction.

[0020] As will be described below, the control unit 6 calculates the amount of movement of the lens 11 constituting the lens group 10. Based on the calculated amount of movement, the control unit 6 controls the drive unit 5 to move the lens 11 constituting the lens group 10. By adjusting the position of the lens 11 in this way, the adjustment device can reduce the transmitted wavefront aberration of the lens group 10.

[0021] In this embodiment, the control unit 6 calculates each aberration component of the transmitted wavefront aberration. The aberration components include spherical aberration, astigmatism, coma, and field curvature. In the symbols used below, those relating to spherical aberration are given the suffix SP. Those relating to astigmatism are given the suffix AS. Those relating to coma are given the suffix CM. Furthermore, those relating to field curvature are given the suffix FC.

[0022] First, the calculation formula will be explained using spherical aberration (SP) as an example. ＳＰ is the spherical aberration of the lens group 10 before adjustment. ＳＰ is the target value of the transmitted wavefront aberration that relates to the spherical aberration, that is, the target value of the spherical aberration. １ , x ２ , x ３ , x ４ (See FIG. 2) changes, the amount of change is Δx １ , Δx ２ , Δx ３ , Δx ４ In this case, the following equation (a) holds for appropriate adjustment parameters.

[0023]

[0024] Here, Δf ＳＰ / Δx １ is the air gap x １ Δx １ is the rate of change of spherical aberration when the angle Δf is changed by ＳＰ / Δx ２ is the air gap x ２ Δx ２ is the rate of change of spherical aberration when the angle Δf is changed by ＳＰ / Δx ３ is the amount of eccentricity x ３ Δx ３ is the rate of change of spherical aberration when the angle Δf is changed by ＳＰ / Δx ４ is the amount of eccentricity x ４ Δx ４Hereinafter, these rates of change may be referred to as the sensitivity of the lens 11 that constitutes the lens group 10.

[0025] As in the case of spherical aberration, the following equations (b) to (d) hold for astigmatism, coma, and field curvature.

[0026]

[0027] If it is linear, the following equations (e) to (g) hold, and as shown in equation (g), the transmitted wavefront aberration becomes the target value X(x １ , x ２ , x ３ and x ４ That is, the control unit 6 can calculate, based on X, the amount of movement of the lens 11 that will cause the transmitted wavefront aberration of the lens group 10 to reach the target value.

[0028]

[0029] Here, after the lens 11 is moved according to X calculated above, the transmitted wavefront aberration of the lens group 10 ideally reaches the target value. However, in reality, the transmitted wavefront aberration behaves nonlinearly with respect to the adjustment parameters, rather than linearly as assumed above. Therefore, in this embodiment, the control unit 6 uses an evaluation function to evaluate the lens group 10 after the lens 11 is moved, and performs optimization so that the transmitted wavefront aberration approaches the target value. In this embodiment, the control unit 6 uses the Newton-Raphson method for finding an optimal solution, as shown in FIG. 5 . That is, the control unit 6 uses the Newton-Raphson method for finding an optimal solution by iterative linear solution, gradually moving each of the adjustment parameters, and then recalculating the sensitivity of the lens 11 after each movement, repeating this process. The horizontal axis in FIG. 5 represents the value of X. The vertical axis represents the value of the evaluation function Φ. Weighting for spherical aberration, astigmatism, coma, and field curvature is expressed as w ＳＰ , w ＡＳ , w ＣＭ , w ＦＣ Then, the evaluation function Φ is expressed by the following formula (h).

[0030]

[0031] When spherical aberration, astigmatism, coma, and field curvature are all at their target values, the evaluation function Φ becomes zero. Since it is practically difficult to set all of them to their target values, the adjustment end condition may be that the value of the evaluation function Φ is smaller than a first predetermined value. Here, the adjustment end condition is a condition for ending the adjustment of the lens group 10. The first predetermined value is determined, for example, based on the optical performance required of the lens group 10 and the evaluation function Φ.

[0032] The control unit 6 determines whether the value of X obtained by the above calculation is X ｔ０ If it was, X ｔ０ If the value of the evaluation function Φ in does not satisfy the adjustment termination condition, ｔ０ The above calculation is performed again for the lens group 10 after the lens 11 is moved based on ｔ１ Here, in the Newton-Raphson method, the value of X is X ｔ０ If ｔ０ The intercept of the tangent at X ｔ１ By repeating this process, an approximate solution is found where the evaluation function Φ becomes zero. ｔ０ To find the tangent at X ｔ０ This corresponds to calculating the above A (sensitivity of the lens 11) in the lens group 10 after the lens 11 is moved based on the new intercept X ｔ１ Finding corresponds to calculating a new value of X using the calculated A. If the value of the evaluation function Φ does not satisfy the adjustment termination condition, the optimal solution can be obtained by repeating the above calculation.

[0033] In the Newton-Raphson method, as shown in FIG. ｔｐ and X ｔ（ｐ＋１） It may happen that the value calculated between and does not converge to a single value of X. To avoid this, ｔｐ From X ｔ（ｐ＋１） As an example, a limit may be placed on the amount of change to x １ , x ２ , x ３ and x ４A limit may be set so that the change in each of these is converted to 10 μm or less. In order to set such a limit, the control unit 6 may obtain an optimal solution by the DLS (Damping Least Square) method instead of the Newton-Raphson method. For example, when the DLS method is used, the control unit 6 may calculate the following formula (i) instead of the above formula (g) with d as the damping constant and E as the unit matrix. Furthermore, the evaluation function Φ may be the following formula (j) with the change in X being ΔX.

[0034]

[0035] Contrary to the example in FIG. 6, if the value of X is almost converged to one, ｔｐ From X ｔ（ｐ＋１） Therefore, the control unit 6 may set the adjustment termination condition to be that the amount of movement of the lens 11 constituting the lens group 10 is smaller than a second predetermined value. The second predetermined value is determined based on, for example, the evaluation function Φ.

[0036] Here, the adjustment termination condition is not limited to one and may include multiple conditions. The control unit 6 may terminate the adjustment of the lens group 10 when any one of the multiple conditions included in the adjustment termination condition is satisfied. In other words, the adjustment termination condition may include the value of the evaluation function for the transmitted wavefront aberration being smaller than a first predetermined value and the movement amount of the lens 11 constituting the lens group 10 being smaller than a second predetermined value. Furthermore, the field curvature (FC) is measured by mounting the light source 1 on a uniaxial stage, mounting the light receiving system 3 and the wavefront sensor 4 on another uniaxial stage, and moving the light source 1 to a position away from the optical axis. In this measurement, the position of the wavefront sensor 4 is the light-focusing position of the lens group 10. The field curvature is obtained from the difference between the focus component (Foc(0)) obtained from the wavefront sensor 4 when the light source 1 is on the optical axis and the focus component (Foc(r)) obtained from the wavefront sensor 4 when the light source 1 is moved to a position away from the optical axis. The field curvature is calculated as FC = Foc(r) - Foc(0). Multiple measurement points may be used when the light source 1 is moved away from the optical axis, and the field curvature can be determined by assigning an appropriate sign to the maximum absolute value of the difference between the focus components. Similarly to the field curvature measurement, the distortion aberration (DS) is measured by mounting the light source 1 on a uniaxial stage and mounting the light-receiving system 3 and wavefront sensor 4 on a separate uniaxial stage. In this measurement, the position of the wavefront sensor 4 is the light-focus position defined by the lens group 10. First, the position of the uniaxial stage (PS(0)) when the light source 1 is on the optical axis and the position of the uniaxial stage (PD(0)) on which the wavefront sensor 4 is mounted are used as references. The position of the uniaxial stage (PD(r)) on which the wavefront sensor 4 is mounted is determined relative to the position of the uniaxial stage (PS(r)) of the light source 1 when the light source 1 is moved away from the optical axis. The difference between the moving distance of the wavefront sensor 4 and the value obtained by multiplying the moving distance of the light source 1 by the magnification (β) of the lens group 10 is the distortion difference. The distortion difference is calculated as DS=PD(r)-PD(0)-β{PS(r)-PS(0)}.

[0037] 7 is a flowchart illustrating an adjustment method according to an embodiment of the present disclosure. The adjustment device performs processing according to the flowchart of FIG. 7 to automatically adjust the lenses 11 that constitute the lens group 10 so that the lens group 10 can achieve desired optical performance.

[0038] The adjustment device measures the initial aberration, which is the transmitted wavefront aberration of the lens group 10 (step S1). More specifically, the control unit 6 calculates the transmitted wavefront aberration (initial aberration) of the lens group 10 before moving the lens 11, based on information from the wavefront sensor 4. Here, step S1 corresponds to the first step and the first processing executed by the control unit 6.

[0039] The adjustment device moves the lens 11 constituting the lens group 10 and measures a plurality of transmitted wavefront aberrations (step S2). More specifically, the control unit 6 controls the drive unit 5 to move the lens 11 so as to change one adjustment parameter. Based on information from the wavefront sensor 4, the control unit 6 calculates the transmitted wavefront aberration of the lens group 10 for which one adjustment parameter has been changed. The control unit 6 returns the moved lens 11 to its original position via the drive unit 5. Thereafter, the movement of the lens 11, the calculation of the transmitted wavefront aberration, and the movement of the lens 11 to its original position are repeated so as to change another adjustment parameter, thereby measuring a plurality of transmitted wavefront aberrations. In step S2, the amount of change (Δx １ , Δx ２ , Δx ３ , Δx ４ ) and the transmitted wavefront aberration after each change are measured. Here, step S2 corresponds to the second step and the second processing executed by the control unit 6.

[0040] The adjustment device calculates the sensitivity of the lenses 11 constituting the lens group 10 based on the amount of change from the initial aberration of the measured multiple transmitted wavefront aberrations (step S3). More specifically, the control unit 6 compares the multiple transmitted wavefront aberrations calculated in step S2 with the initial aberration. In this embodiment, the control unit 6 calculates the amount of change (Δf ＳＰ , Δf ＡＳ , Δf ＣＭ , Δf ＦＣ The control unit 6 calculates the sensitivity of the lens 11 constituting the lens group 10 based on the amount of change in each aberration component of the transmitted wavefront aberration and the amount of change in the adjustment parameter. Here, step S3 corresponds to the third step and the third process executed by the control unit 6.

[0041] The adjustment device calculates the amount of movement of the lens 11 constituting the lens group 10 based on the calculated sensitivity (step S4). The control unit 6 calculates the amount of movement of the lens 11 by, for example, the above formula (g) so that the transmitted wavefront aberration becomes the target value. Here, step S4 corresponds to the fourth step and the fourth process executed by the control unit 6.

[0042] The adjustment device moves the lenses 11 constituting the lens group 10 based on the calculated movement amount (step S5). The control unit 6 causes the drive unit 5 to move the lenses 11 constituting the lens group 10 based on the calculated movement amount. Here, step S5 corresponds to the fifth step and the fifth process executed by the control unit 6.

[0043] The adjustment device evaluates the lens group 10 after the lens 11 has moved based on the calculated movement amount (step S6). In this embodiment, the control unit 6 performs the evaluation using the above-mentioned evaluation function Φ. Here, step S6 corresponds to the sixth step and the sixth process executed by the control unit 6.

[0044] If the adjustment device determines from the evaluation result that the adjustment termination condition is not satisfied (No in step S7), it performs steps S2 to S6 again without replacing the lenses 11 and the lens barrel 12 that constitute the lens group 10. By repeating steps S2 to S6, optimization is performed so that the transmitted wavefront aberration approaches the target value. If the adjustment device determines that the adjustment termination condition is satisfied (Yes in step S7), it considers that the transmitted wavefront aberration of the lens group 10 approaches the target value and terminates the adjustment.

[0045] As described above, the adjustment method and adjustment device according to this embodiment can automatically adjust the lens group 10 to obtain the desired optical performance, using the above-described configuration and process, without replacing the lens 11 and the lens barrel 12 with other items (replacement components).

[0046] Although the embodiments of the present disclosure have been described based on the drawings and examples, it should be noted that those skilled in the art would easily be able to make various modifications or alterations based on the present disclosure. Therefore, it should be noted that these modifications and alterations are included within the scope of the present disclosure. For example, functions included in each component or step can be rearranged so as not to be logically inconsistent, and multiple components or steps can be combined or divided into one. The embodiments of the present disclosure can also be realized as a program executed by a processor included in an apparatus or a storage medium on which a program is recorded. It should be understood that these are also included within the scope of the present disclosure.

[0047] For example, the configuration of the adjustment device is not limited to the configuration shown in FIG. 1 . FIGS. 8 to 10 are diagrams showing other configuration examples of the adjustment device. As shown in FIG. 8 , the adjustment device may have a configuration in which the incident optical system 2 is omitted from the configuration shown in FIG. 1 . For example, if the lens group 10 is a finite system, the incident optical system 2 may be unnecessary. Furthermore, as shown in FIG. 9 , the adjustment device may have a configuration in which the light-receiving system 3 is omitted from the configuration shown in FIG. 1 . For example, if the lens group 10 is an afocal system and the light beam diameter fits within the size of the light-receiving section of the wavefront sensor 4, the light-receiving system 3 may be unnecessary. However, if the lens group 10 is an afocal system and the light beam diameter does not fit within the size of the light-receiving section of the wavefront sensor 4, the light-receiving system 3 may be configured to include a beam expander, as shown in FIG. 10 . Here, in an adjustment device configured to use the light-receiving system 3 (for example, FIGS. 1 , 8 , and 10 ), the position of the light-receiving system 3 is adjusted so that the exit pupil of the lens group 10 is projected onto the light-receiving surface of the wavefront sensor 4.

[0048] The control unit 6 may use other methods, such as an orthogonalization method, an annealing method, or a genetic algorithm, instead of the Newton-Raphson method or the DLS method, as the method for performing the above optimization.

[0049] In the above embodiment, the aberration components of the transmitted wavefront aberration have been described as including spherical aberration, astigmatism, coma, and field curvature, but may further include distortion. Furthermore, the aberration components of the transmitted wavefront aberration may include chromatic aberration of magnification. Furthermore, the aberration components of the transmitted wavefront aberration may be aberrations corresponding to individual positions on the image plane. Here, the transmitted wavefront aberration does not need to include multiple types of aberration components, and may include only one type of aberration exemplified above. Furthermore, the aberration components of the transmitted wavefront aberration may be coefficients of a Zernike polynomial.

[0050] In the above embodiment, the driver 5 moves the lens 11 in the optical axis direction and in a direction perpendicular to the optical axis direction. Here, the direction of movement of the lens 11 by the driver 5 may be only in the optical axis direction or only in a direction perpendicular to the optical axis direction. In other words, the driver 5 may move the lens 11 in at least one of the optical axis direction and a direction perpendicular to the optical axis direction.

[0051] As described with reference to FIG. 6 , for example, the control unit 6 may issue a notification to the user of the adjustment device requesting a response when an optimal solution cannot be obtained. The user of the adjustment device may be, for example, an operator of adjustment work in the manufacture of a lens assembly. For example, when the control unit 6 determines that the adjustment termination condition is not satisfied after the second to sixth steps have been repeated a predetermined number of times, the control unit 6 may notify the user to replace at least one of the lens 11 and the lens barrel 12 constituting the lens group 10. For example, if the control unit 6 is a computer, the notification may be made by at least one of displaying on a display connected to the computer and outputting audio to a speaker. The predetermined number of times is not particularly limited, but may be 10 times, for example.

[0052] REFERENCE SIGNS LIST 1 Light source 2 Incident optical system 3 Light receiving system 4 Wavefront sensor 5 Driving unit 6 Control unit 10 Lens group 11 Lens 12 Lens barrel 13 Spacer 14 Screw

Claims

1. A first step of measuring an initial aberration which is the transmitted wavefront aberration of a lens group accommodated in a lens barrel; A second step of moving the lenses constituting the lens group in at least one of the optical axis direction and a direction orthogonal to the optical axis direction to measure a plurality of transmitted wavefront aberrations; A third step of calculating the sensitivity of the lenses constituting the lens group based on the amount of change from the initial aberration of the plurality of measured transmitted wavefront aberrations; A fourth step of calculating the amount of movement of the lenses constituting the lens group based on the calculated sensitivity; A fifth step of moving the lenses constituting the lens group based on the calculated amount of movement; A sixth step of evaluating the lens group in which the lenses have moved based on the calculated amount of movement, and including: An adjustment method, in which when it is determined from the result of the evaluation that the adjustment end condition is not satisfied, the second to sixth steps are performed again without replacing the lenses constituting the lens group and the lens barrel.

2. The adjustment method according to claim 1, wherein the adjustment end condition includes that the value of the evaluation function for the transmitted wavefront aberration is smaller than a first predetermined value.

3. The adjustment method according to claim 1 or 2, wherein the adjustment end condition includes that the amount of movement is smaller than a second predetermined value.

4. The adjustment method according to claim 1 or 2, including a step of notifying that at least one of the lenses constituting the lens group and the lens barrel is to be replaced when it is determined that the adjustment end condition is not satisfied after repeating the second to sixth steps a predetermined number of times.

5. An incident optical system that causes light emitted from a light source to be incident on a lens group accommodated in a lens barrel; A light receiving system that receives light transmitted through the lens group; A wavefront sensor that receives light through the light receiving system; A drive unit that moves the lenses constituting the lens group; A control unit, and The control unit A first process of calculating an initial aberration which is the transmitted wavefront aberration of the lens group based on information from the wavefront sensor; A second process of moving the lenses constituting the lens group in at least one of the optical axis direction and a direction orthogonal to the optical axis direction by the drive unit, and calculating a plurality of transmitted wavefront aberrations based on information from the wavefront sensor; A third process of calculating the sensitivity of the lenses constituting the lens group based on the amount of change from the initial aberration of the plurality of calculated transmitted wavefront aberrations; A fourth process of calculating a movement amount of a lens constituting the lens group based on the calculated sensitivity; A fifth process of moving a lens constituting the lens group to the drive unit based on the calculated movement amount; A sixth process of evaluating the lens group in which the lens has moved based on the calculated movement amount; and An adjustment device that, when it is determined from the result of the evaluation that the adjustment end condition is not satisfied, performs the second process to the sixth process again without replacing the lens constituting the lens group and the lens barrel.