JP5544765B2 - Wavefront shape measuring apparatus and wavefront shape measuring method - Google Patents

Description

  The present invention relates to a wavefront shape measuring apparatus and a wavefront shape measuring method for measuring a wavefront shape of light passing through a test object such as a camera lens, a microscope objective lens, and a mirror by the Shack-Hartmann method.

  Conventionally, when inspecting an optical system that uses white light, such as a camera lens, a pinhole image or a slit image of a lens to be examined by a white light source has been observed.

  However, in recent years, it has become more common to measure the wavefront shape after passing the light emitted from the laser light source into the test lens and passing through the test lens. This is because the wavefront shape contains more information than the pinhole image or the slit image.

  An interferometer and a Shack-Hartmann sensor are effective for measuring such a wavefront shape. In particular, the Shack-Hartmann sensor is known to have a wide dynamic range (see Patent Document 1).

JP 2005-98933 A

  However, an optical system with a wide field of view such as a camera lens has a high possibility that a large aberration remains as compared with an optical system with a narrow field of view such as a microscope objective lens. In particular, a wide-angle camera lens has a large aberration around the visual field. For this reason, when a camera lens is used as a test lens, there is a possibility that even a Shack-Hartmann sensor cannot be measured.

  Under such circumstances, the present invention provides a Shack-Hartmann-type wavefront shape measuring method capable of reliably performing measurement irrespective of the quality of the test object (the degree of aberration and shape error), and the wavefront thereof. A Shack-Hartmann type wavefront shape measuring apparatus suitable for a shape measuring method is provided.

One aspect illustrating the wavefront shape measuring apparatus of the present invention includes a microlens array that individually collects each partial light beam of a test light beam that has passed through a test object, and a condensing point of each partial light beam by the microlens array. Detecting means for acquiring array data; wavefront deforming means for superimposing a predetermined shape component on the wavefront of the light beam to be detected toward the microlens array; and adjusting the shape component that the wavefront deforming means should superimpose on the wavefront Shape adjusting means , measuring means for acquiring array data relating to the test light beam on which the adjusted shape component is superimposed, measurement data, correction data acquiring means for acquiring correction data indicating the adjusted shape component, and measurement data And correction means for acquiring corrected measurement data by correcting the correction data with correction data .

One aspect illustrating the wavefront shape measuring method of the present invention is a wavefront shape measuring method using one aspect illustrating the wavefront shape measuring apparatus of the present invention, and the shape adjustment is performed with reference to the array data acquired by the detecting means. An adjustment procedure for driving the means to make the interval between adjacent condensing points equal to or greater than a threshold value, a measurement procedure for acquiring array data relating to the test light beam on which the adjusted shape component is superimposed , and adjustment A correction data acquisition procedure for acquiring correction data indicating the subsequent shape component and a correction procedure for acquiring the measurement data after correction by correcting the measurement data with the correction data are included.

  INDUSTRIAL APPLICABILITY According to the present invention, it is suitable for the Shack-Hartmann wavefront shape measuring method and the wavefront shape measuring method capable of reliably performing the measurement regardless of the quality of the test object (aberration or shape error). A Shack-Hartmann-type wavefront shape measuring device is realized.

The block diagram of the apparatus of this embodiment. The figure explaining the arrangement | sequence of a spot when the aberration of the to-be-tested lens 10 is small. The figure explaining the arrangement | sequence of a spot when the aberration of the to-be-tested lens 10 is large. The figure which shows the arrangement | sequence of a spot when the aberration of the to-be-tested lens 10 is small and the collimating lens 15 is in a defocusing state. The figure which shows the arrangement | sequence of a spot when the aberration of the to-be-tested lens 10 is large and the collimating lens 15 is a defocus state. The operation | movement flowchart of the control part at the time of a measurement. The figure explaining the state of the apparatus at the time of a measurement. The schematic diagram explaining each data. The operation | movement flowchart of the control part at the time of a chasing process. The block diagram of a double pass type measuring device.

  Hereinafter, a Shack-Hartmann wavefront shape measuring apparatus will be described as a first embodiment of the present invention.

  FIG. 1 is a configuration diagram of an apparatus according to the present embodiment. The apparatus includes a laser light source (not shown), an optical fiber 11 connected to the laser light source, a condenser lens 12, a pinhole plate 13 for generating a point light source, a collimator lens 14, a collimator lens 15, A two-dimensional microlens array 16, a two-dimensional light receiving element array 17, a lens driving mechanism 18, a light source moving mechanism 19, and a control unit (not shown) are arranged, and between the collimator lens 14 and the collimator lens 15. A test lens 10 such as a camera lens is set. Note that a laser is preferable as the light source of this apparatus, but it is not always necessary to be a laser. Further, the optical fiber 11 shown in FIG. 1 may be a bundle fiber.

  The light beam emitted from the emission end of the optical fiber 11 illuminates the pinhole of the pinhole plate 13 through the condenser lens 12. Thereby, a point light source is formed at the position of the pinhole. The light beam (ideal spherical wave) emitted from the pinhole becomes a parallel light beam through the collimator lens 14 and enters the lens 10 to be examined. The light beam (test light beam) that has passed through the test lens 10 is once condensed and then incident on the collimator lens 15 while diverging. The test light beam incident on the collimator lens 15 is made close to a parallel light beam by the collimator lens 15 and then enters the microlens array 16. Of the test light beam incident on the microlens array 16, the partial light beams incident on the individual microlenses (lenslets) of the microlens array 16 are condensed to form spots on the light receiving element array 17.

  When the position of the collimator lens 15 in the optical axis direction is set to the reference position A and the aberration of the test lens 10 is zero, the wavefront of the test light beam incident on the microlens array 16 is as shown in FIG. The arrangement of the plurality of spots that are flat and formed on the light receiving element array 17 is an arrangement corresponding to the arrangement of the microlenses.

  On the other hand, when the position of the collimator lens 15 in the optical axis direction is set to the reference position A and the aberration of the test lens 10 is not zero, the test light beam incident on the microlens array 16 as shown in FIG. The wavefront is non-planar, and the arrangement of the plurality of spots formed on the light receiving element array 17 is an arrangement corresponding to the arrangement of the microlenses.

  A control unit (not shown) calculates an array of a plurality of spots (for example, an array of the center of gravity of the spots) based on the output of the light receiving element array 17, and the test lens 10 gives the wavefront of the test light beam based on the array. An aberration component is calculated.

  Here, as shown in FIG. 2, when the aberration of the test lens 10 is small, the arrangement of the spots is almost the same as the arrangement of the microlenses, but the aberration of the test lens 10 is large as shown in FIG. In some cases, the arrangement of spots is different from the arrangement of microlenses, and there is a possibility that overlap occurs between adjacent spots.

  If an overlap occurs between adjacent spots, the control unit cannot accurately determine the arrangement of the spots from the output of the light receiving element array 17, and the aberration given by the test lens 10 to the wavefront of the test light beam. It becomes difficult to calculate the components.

  Therefore, the lens driving mechanism 18 shown in FIG. 1 shifts the collimator lens 15 from the reference position A in the direction of the arrow (optical axis direction) in accordance with an instruction from the control unit, so that the collimator lens 15 is brought into a defocused state. To do. When the collimator lens 15 is in a defocused state, the defocusing causes a convex spherical component to be superimposed on the wavefront of the test light beam as shown in FIGS. 4 is a diagram showing the arrangement of spots when the test lens 10 has a small aberration and the collimator lens 15 is in a defocused state. FIG. 5 shows a test lens 10 having a large aberration. It is a figure which shows the arrangement | sequence of the spot when the collimating lens 15 is a defocus state. 4 and 5 show only the principal rays of the partial light beams.

  Moreover, as the defocus amount of the collimator lens 15 is larger, the power of the spherical component superimposed on the wavefront of the test light beam is larger, so that the spot interval is larger.

  Here, a phenomenon that occurs when a spherical component is superimposed on a wavefront will be described in detail using mathematical expressions.

  First, the arrangement pitch of microlenses (lens lots) in the microlens array 16 is d, the coordinates on the microlens array 16 are represented by (x, y), and the coordinates on the light receiving element array 17 are (x ′, y ′). ). However, the origin of these coordinates is set at the center of the microlens array 16 and the light receiving element array 17.

At this time, paying attention to the (i, j) th microlens, the coordinates (x, y) of the center position P of the microlens are expressed by the following formula (1) (hereinafter, this microlens is expressed as “ This is referred to as a “focused microlens”.)
x = i · d, y = j · d (1)
Therefore, when the wavefront incident on the microlens array 16 is a plane wave as shown in FIG. 2, the coordinates (x, y) of the center position P of the target microlens and the light beam that has passed through the target microlens are on the light receiving element array 17. The relationship with the coordinates (x ′, y ′) of the spot position Q to be formed is expressed by the following equation (2).
x ′ = x = i · d, y ′ = y = j · d (2)
On the other hand, as shown in FIG. 4, when the wavefront incident on the microlens array 16 is a convex spherical wave, the spot position Q is shifted outward, so that equation (2) does not hold, and equations (6) and (7) described later are not satisfied. ) Holds.

This is because the wavefront w (x, y) of the spherical wave incident on the microlens array 16 is represented by a quadratic function as shown in the following equation (3).
w (x, y) = α · (x ² + y ² ) (3)
In this case, the deviation amount of the spot position Q as described above (.delta.x ', .delta.y') has the following formula with respect to the focal length f _m of the microlens (4) is expressed by (5).

Therefore, when the wavefront incident on the microlens array 16 is a convex spherical wave, the relationship between the coordinates (x, y) of the position P and the coordinates (x ′, y ′) of the position Q is expressed by the following equation (6). ) And (7).
x '= i · d + δx ' = i · d · (1 + 2 · α · f m) ... (6)
y '= j · d + δy ' = j · d · (1 + 2 · α · f m) ... (7)
As is clear from comparison between these equations (6) and (7) and the above equation (2), when the wavefront incident on the microlens array 16 is changed from a plane wave to a convex spherical wave, the microlens array 16 pitch d of (1 + 2 · α · f m) it can be seen that the equivalent behavior doubling occurs.

  Therefore, the control unit of the present embodiment sets the defocus amount of the collimator lens 15 in accordance with the amount of aberration of the lens 10 to be tested, thereby setting the spot interval to a certain value or more.

  However, if the spherical component superimposed on the wavefront of the test light beam due to defocusing of the collimator lens 15 is not known, the aberration component given to the wavefront of the test light beam by the test lens 10 cannot be calculated. The preliminary measurement described later is performed to make it known.

  The light source moving mechanism 19 shown in FIG. 1 is a mechanism provided for preliminary measurement. The light source moving mechanism 19 moves the light source unit 20 including the emission end of the optical fiber 11, the condenser lens 12, and the pinhole plate 13 in the optical axis direction in accordance with an instruction from the control unit. The position (that is, the point light source formation position) is shifted in the optical axis direction. Here, the movement target of the light source moving mechanism 19 is the entire light source unit 20, but only the pinhole plate 13 or only the pinhole plate 13 and the condenser lens 12 may be used.

  FIG. 6 is an operation flowchart of the control unit during measurement. Hereinafter, each step will be described in order.

  Step S11: The control unit monitors whether or not an instruction to start the main measurement is input. The control unit waits as it is when the main measurement start instruction is not input, and when the main measurement start instruction is input, the control unit proceeds to step S12. When starting the main measurement, the user inputs the main measurement start instruction to the control unit when the lens 10 to be tested is set in the apparatus.

  Step S12: The control unit sets the position of the collimator lens 15 in the optical axis direction to the reference position A as shown in FIG. Note that the control unit stores in advance the focal length f of the collimator lens 15 and the focal length of the lens 10 to be tested. In this step, the collimator lens 15 and the lens 10 to be tested are determined according to the focal length. By adjusting the relative position in the optical axis direction, the focal position of the collimator lens 15 and the focal position of the lens 10 to be tested are matched. The position of the collimator lens 15 in this state is the reference position A.

  Step S13: The control unit acquires array data of a plurality of spots formed on the light receiving element array 17 based on the output of the light receiving element array 17, and sets it as measurement data D1 (see the upper left in FIG. 8). The array data referred to here is data indicating each spot position (for example, barycentric coordinates) of a plurality of spots formed on the light receiving element array 17.

  Step S14: The control unit determines whether or not the interval between the two closest spot positions among the plurality of spot positions included in the measurement data D1 is equal to or greater than a threshold value. The process proceeds to S15, and if it is equal to or greater than the threshold, the process proceeds to step S16. However, the control unit in this step refers to the number of spot positions included in the measurement data D1, and when the number is less than the number of effective microlenses, any two or more of the plurality of spots are included. It is considered that the spots overlap each other, and the process proceeds to step S15 regardless of the size of the above-described interval.

  Step S15: The control unit shifts the collimator lens 15 by one step from the reference position A in the direction of the arrow (increases the defocus amount of the collimator lens 15 by one step), and then returns to step S12. Therefore, even if the aberration of the lens 10 to be measured is large and the minimum interval between the spot positions at the end of step S12 is smaller than the threshold value, the loop between steps S13, S14, and S15 is repeated to repeat the minimum interval between the spot positions. Approaches the threshold. FIG. 7B shows the optical arrangement when the number of loop iterations is sufficient and the minimum spot position interval is equal to or greater than a threshold value. In this state, the position A ′ of the collimator lens 15 in the optical axis direction is closer to the test lens 10 than the reference position A.

  Step S16: The control unit notifies the user that the main measurement is completed, and monitors whether a preliminary measurement start instruction is input. When starting the preliminary measurement, when the user removes the lens 10 and the collimator lens 14 from the optical path, the user inputs a preliminary measurement start instruction to the control unit. Note that in a state where the test lens 10 is removed from the optical path, the light beam incident on the collimator lens 15 is a light beam that does not pass through the test lens 10 (calibration light beam). If the preliminary measurement start instruction is not input, the control unit stands by, and if the preliminary measurement start instruction is input, the control unit proceeds to step S17.

  Step S17: The control unit sets the position of the pinhole plate 13 in the optical axis direction, that is, the position of the light source of the calibration light beam to the focal position (reference position B) of the collimator lens 15 as shown in FIG. . The control unit stores the focal length f of the collimator lens 15 in advance, and drives the light source unit 20 in accordance with the focal length f, thereby determining the position of the pinhole plate 13 in the optical axis direction as the reference position B. Set to.

  Step S18: Based on the output of the light receiving element array 17, the control unit acquires array data of a plurality of spots formed on the light receiving element array 17 as correction data D2 (see the upper right in FIG. 8).

  Step S19: The control unit obtains the corrected measurement data (measurement data D3) by subtracting the correction data D2 from the measurement data D1 (see the lower part of FIG. 8). The measurement data D3 is data obtained by calculating the difference between the spot position included in the measurement data D1 and the spot position included in the correction data D2 for each spot.

  Step S20: The control unit calculates the RMS value of each difference included in the measurement data D3, and the RMS value has not converged to the minimum value (when the amount of change from the previous value is greater than or equal to the threshold value). If the RMS value has converged to the minimum value (if the amount of change from the previous value is less than the threshold value), the process proceeds to step S22.

  Step S21: The control unit shifts the pinhole plate 13 from the reference position B in the direction of the arrow by one step (increases the defocus amount of the pinhole plate 13 by one step), and then returns to step S18. . Therefore, by repeating the loop of steps S18, S19, S20, and S21, the above-described RMS value approaches the minimum value. Note that the symbol B ′ in FIG. 7C indicates the position of the pinhole plate 13 when the loop is sufficiently repeated and the RMS value becomes the minimum value. The wavefront of the calibration light beam when the position of the pinhole plate 13 is the position B ′ indicates a spherical component superimposed on the wavefront of the test light beam by the defocusing of the collimator lens 15 shown in FIG. Therefore, the correction data D2 at the time when the repetition of the loop is completed indicates a spherical component superimposed on the wavefront of the test light beam by the defocusing of the collimator lens 15 shown in FIG. Therefore, the measurement data D3 at the time when the loop is completed indicates the aberration component given to the wavefront of the test light beam by the test lens 10.

  Step S22: The control unit calculates the distance from the reference position B to the position B based on the movement amount of the pinhole plate 13 before and after the loop is repeated, and stores it as the defocus amount δ of the pinhole plate 13. The defocus amount δ corresponds to the distance from the reference position A to the position A ′ shown in FIG. 7B, that is, the defocus amount of the collimator lens 15. This defocus amount δ is used in a follow-up process to be described later.

  Step S23: The control unit fits a predetermined polynomial (for example, a derivative of Zernike polynomial) expressing wavefront aberration to the measurement data D3, and integrates the polynomial obtained by the fitting, The aberration component (that is, wavefront aberration) given by the lens 10 to the wavefront of the test light beam is restored. Then, the control unit stores the restored wavefront aberration as a measurement result and displays it on a monitor (not shown), and ends the flow.

  FIG. 9 is an operation flowchart of the control unit during the follow-up process. Each step will be described in turn.

  Step S31: The control unit monitors whether or not an instruction for starting the follow-up process is input. When the user refers to the wavefront aberration displayed on a monitor (not shown) and determines that the follow-up process (further accuracy improvement) is necessary, the user inputs a start-up instruction for the follow-up process to the control unit. The control unit waits as it is when an instruction to start the chasing process is not input, and proceeds to step S32 when an instruction to start the chasing process is input.

  Step S32: The control unit sets the initial value of the wavefront aberration model of the test lens 10 to be the same as the wavefront aberration acquired in the previous step S23.

  Step S33: The control unit performs a simulation (light ray) based on the wavefront aberration model of the lens 10 to be examined, the optical system design data from the pinhole to the light receiving element array 17, and the defocus amount δ acquired in the previous step S22. By tracking), array data generated by the optical system in the state of FIG. 7B is calculated. This array data corresponds to the calculated value of the measurement data D1 acquired in the state of FIG. Therefore, hereinafter, the array data is referred to as “calculation data D1 ′”.

  Step S34: The control unit obtains the difference data D4 by subtracting the measurement data D1 from the calculation data D1 '. The difference data D4 is data obtained by calculating the difference between the spot position included in the calculation data D1 'and the spot position included in the measurement data D1 for each spot.

  Step S35: The control unit calculates the RMS value of each difference included in the difference data D4, and the RMS value has not converged to the minimum value (when the amount of change from the previous value is greater than or equal to the threshold value). If the RMS value has converged to the minimum value (if the amount of change from the previous value is less than the threshold value), the process proceeds to step S37.

  Step S36: The control unit adjusts the wavefront aberration model, and then returns to step S33.

  Step S37: The control unit stores the current wavefront aberration model as a final measurement result of the wavefront aberration and displays it on a monitor (not shown), and ends the flow.

  As described above, the collimator lens 15 and the lens driving mechanism 18 of the present embodiment generate the microlens array 16 by intentionally superimposing a predetermined shape component (here, a spherical component) on the wavefront of the test light beam. Increase the spacing between multiple spots. Therefore, even if the aberration of the test lens 10 is large, the overlap between spots can be avoided.

  Further, the collimator lens 15 and the lens driving mechanism 18 of the present embodiment can change the degree of the shape component to be intentionally superimposed (here, the power of the spherical component). Therefore, the apparatus of the present embodiment can cope with various test lenses having different aberration amounts.

  In addition, since the collimator lens 15 and the lens driving mechanism 18 of the present embodiment use a simple spherical component as a shape component that is intentionally overlapped, it is possible to easily and reliably avoid overlapping of spots.

  Further, the apparatus according to the present embodiment uses the collimator lens 15 as means for superimposing a predetermined shape component on the wavefront of the test light beam, and uses the lens driving mechanism 18 as means for changing the degree of the shape component. Therefore, there is no need to insert a dedicated optical system in the measurement optical path.

  In addition, the control unit of the present embodiment acquires measurement data D1 in a state where the spot interval is equal to or greater than the threshold, and correction data D2 corresponding to the shape component that the collimator 15 superimposes on the wavefront of the test light beam by defocusing. Is subtracted from the measurement data D1 to obtain measurement data D3. Therefore, the control unit can acquire the aberration component given to the test light beam by the test lens 10 as the measurement data D3.

  Further, the control unit of the present embodiment causes the calibration light beam to enter the collimator lens 15 instead of the test light beam, and refers to the array data acquired by the light receiving element array 17 in the optical axis direction of the light source of the calibration light beam. By changing the position, the array data is brought close to the measurement data D1, and the array data acquired by the light receiving element array 17 at that time is acquired as the correction data D2. Therefore, the control unit can acquire the shape component given to the test light beam by the collimator lens 15 by defocusing as the correction data D2.

  In addition, since the control unit of the present embodiment performs function fitting on the corrected measurement data D3, the wavefront aberration of the lens 10 to be measured can be restored with high accuracy.

  Further, the control unit of the present embodiment sets the initial value of the wavefront aberration model of the test lens 10 to be the same as the restored wavefront aberration, and then receives light from the wavefront aberration model of the test lens 10 and the pinhole. Array data (calculation data D1 ′) generated by the optical system in the state of FIG. 7B by simulation (ray tracing) based on the design data of the optical system reaching the element array 17 and the defocus amount δ of the pinhole. ) To get. The control unit repeats ray tracing while changing the wavefront aberration model, and uses the wavefront aberration model at the time when the calculation data D1 'is closest to the measurement data D1 as the final measurement result of the wavefront aberration. Therefore, the final measurement result of the wavefront aberration can be obtained with extremely high accuracy.

  In the apparatus of the present embodiment, the correction data D2 is acquired by actual measurement, but may be acquired by calculation.

  In the apparatus of this embodiment, the collimator lens 15 is used as means for superimposing a predetermined shape component on the wavefront of the test light beam, and the lens driving mechanism 18 is used as means for changing the degree of the shape component. Alternatively, one spatial light modulator (such as a liquid crystal modulator) may be inserted into any location on the front side of the microlens array 16 and the spatial light modulator may be shared by these two means. Incidentally, since the spatial light modulation element can deform only a part of the wavefront of the test light beam, the object to be deformed is not the entire wavefront, but only a part of the wavefront (for example, the inclination of the wavefront is steep). Only a portion where the interval between spots becomes narrow may be used. In addition, since the shape component of a single spatial light modulation element superimposed on the wavefront of the test light beam is uniquely determined from the drive signal applied to the spatial light modulation element, correction data is obtained when the spatial light modulation element is used. It is not necessary to actually measure D2.

  In the present embodiment, a part or all of the operation of the control unit may be manually executed by the user, or a part or all of the user operation may be automatically executed by the control unit.

  In the present embodiment, the single-pass type measuring device that detects the wavefront of the test light beam that has passed through the test lens 10 with the Shack-Hartmann sensor has been described. The present invention can also be applied to a double-pass type measuring device that detects with a Shack-Hartmann sensor.

  FIG. 10 is a configuration diagram of a double-pass type measuring apparatus. 10, elements corresponding to those in FIG. 1 are denoted by the same reference numerals. In FIG. 10, reference numeral M indicates a folding mirror (plane mirror), and reference numeral BS indicates a beam splitter. Even in such a double-pass type measuring apparatus, the distance between the spot positions can be increased by moving the collimator lens 15 in the direction of the arrow.

  However, in the double-pass type measuring apparatus, when the lens 10 to be tested is removed from the optical path, it is necessary to insert a spherical mirror instead of the folding mirror M. Incidentally, if the spherical mirror is shifted in the optical axis direction, the same effect as that of defocusing the pinhole plate 13 can be obtained.

  Further, according to the double-pass type measuring apparatus, not only the aberration of the lens but also the shape error of the surface of the mirror or the lens can be measured.

  DESCRIPTION OF SYMBOLS 11 ... Optical fiber, 12 ... Condenser lens, 13 ... Pinhole board, 14 ... Collimator lens, 10 ... Test lens, 15 ... Collimator lens, 16 ... Micro lens array, 17 ... Light receiving element array, 18 ... Lens drive mechanism, 19 ... Light source moving mechanism

Claims (9)

A microlens array that individually collects each partial light beam of the test light beam passing through the test object;
Detecting means for acquiring array data of condensing points of the partial light beams by the microlens array;
Wavefront deformation means for superimposing a predetermined shape component on the wavefront of the test light beam toward the microlens array;
A shape adjusting means for adjusting a shape component to be superimposed on the wavefront by the wavefront deforming means;
Measurement means for acquiring the array data relating to the test light beam on which the shape component after adjustment is superimposed, as measurement data;
Correction data acquisition means for acquiring correction data indicating the shape component after adjustment;
Correction means for acquiring measurement data after correction by correcting the measurement data with the correction data;
A wavefront shape measuring apparatus comprising: The wavefront shape measuring apparatus according to claim 1,
The shape component superposed on the wavefront by the wavefront deforming means is:
A wavefront shape measuring apparatus characterized by being a spherical component. In the wavefront shape measuring apparatus according to claim 2,
The shape adjusting means is
The wavefront shape measuring apparatus characterized by adjusting the power of the spherical component. In the wavefront shape measuring apparatus according to claim 3,
The wavefront deformation means includes
A lens,
The shape adjusting means is
A wavefront shape measuring apparatus characterized by being a mechanism for moving the lens in the optical axis direction. In the wavefront shape measuring apparatus according to any one of claims 1 to 3,
The wavefront shape measuring apparatus, wherein the wavefront deforming means and the shape adjusting means are configured by a common spatial light modulation element. A wavefront shape measuring method using the wavefront shape measuring apparatus according to any one of claims 1 to 5,
An adjustment procedure for driving the shape adjusting means while referring to the array data acquired by the detecting means to set the interval between the condensing points adjacent to each other to a threshold value or more;
A measurement procedure for obtaining, as measurement data, the array data relating to the test light beam on which the shape component after adjustment is superimposed ;
Correction data acquisition procedure for acquiring correction data indicating the shape component after adjustment ;
By correcting the measurement data in the correction data, a correction procedure for acquiring measurement data after correction,
The wavefront shape measuring method characterized by including. The wavefront shape measuring method according to claim 6,
In the correction data acquisition procedure,
After setting the light beam incident on the wavefront deforming means to be a calibration light beam that does not pass through the test object, the position of the light beam of the calibration light beam in the optical axis direction is referred to while referring to the array data acquired by the detecting means. The wavefront shape measuring method, wherein the array data is made closer to the measurement data before correction by changing, and the array data acquired by the detection means in that state is acquired as the correction data. In the wavefront shape measuring method according to claim 6 or 7,
In the correction procedure,
A wavefront shape measuring method, comprising: obtaining characteristic data of the test object by performing function fitting on the corrected measurement data. The wavefront shape measuring method according to claim 8,
After execution of the correction procedure, the design data of the wavefront shape measuring device, the design data of the test object, the characteristic model of the test object, and the driving amount data of the shape adjusting means before and after the adjustment procedure A simulation procedure for calculating a calculated value of the measurement data before correction by simulation based on
The simulation is repeated while changing the characteristic model, and further includes an iterative procedure for calculating the characteristic model at the time when the calculated value is closest to the measurement data before correction as the characteristic of the test object,
An initial value of the characteristic model in the repetition procedure is set to be the same as the characteristic data acquired in the correction procedure.

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