JP2009192249A - Method and device for measuring transmission wave front aberration of test lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device capable of making the optical axis of a test lens coincide with the axis of the interferometer with the circular plane part (R2 plane part), in mounting the test lens as a reference, and thereafter measuring the transmission wave front aberrations with the interferometer, in a measuring method of wave front aberration which measures the wave front aberrations of the test lens, having circular plane parts, respectively at the plane periphery edges of the front and rear lens surface. <P>SOLUTION: A transmission wave front aberration measuring method comprises: a step where in the front and rear circular plane parts of an test lens mounted on a sample base, inclined measuring light is made incident to a mount reference circular planar part which abuts against a lens holder, when the test lens is mounted to detect the inclination amount, from the optical axis of the interferometer of the test lens by the reflection light of the inclination measuring light from the test lens; a step for adjusting the inclination of the sample base, based on the inclination detection amount to coincide the optical axis of the test lens with the optical axis of the interferometer; and a step for measuring the wave front aberrations by the interferometer, in the condition where the optical axes coincide. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method and apparatus for measuring transmitted wavefront aberration of a lens to be examined.

For example, various aberrations of the objective lens (test lens) of the optical pickup are measured as transmitted wavefront aberration by observing interference fringes caused by the transmitted light of the objective lens and the reflected light from the reference surface using an interferometer. ing. In general, the objective lens to be examined is provided with annular plane portions parallel to each other designed to be orthogonal to the optical axis at the periphery of the lens surfaces R1 and R2 on the front and back sides. Either one of the mounting reference annular plane portions (R2 plane portion) is brought into contact with the lens holder. On the other hand, when measuring the transmitted wavefront aberration with an interferometer, the R2 plane plane part is brought into contact with the sample stage, the reflected light on the opposite side (R1 plane plane part) is observed, and the optical axis of the objective lens to be examined is adjusted. Adjustments are made to match the optical axis of the interferometer.
Japanese Patent No. 3581702 JP-A-10-116438 JP 2001-34991 A

  However, in this conventional measuring method, if fine dust adheres to the R2 plane part of the objective lens to be examined or burrs are formed on the R2 plane part, the R2 plane part is brought into close contact with the support surface of the sample stage. Therefore, the measured transmitted wavefront aberration is inaccurate. In other words, the conventional method is based on the premise (expectation) that when the R2 plane portion is placed on the sample stage, the optical axis of the objective lens to be examined and the sample stage optical axis coincide with each other. The correct transmitted wavefront aberration specific to the objective lens to be examined could not be measured. The R1 plane portion and the R2 plane portion are both designed and manufactured as surfaces parallel to each other perpendicular to the optical axis, but if a tilt (wedge) occurs between the two plane portions in the manufacturing process, the correct transmitted wavefront is similarly obtained. Aberration cannot be measured.

  Therefore, according to the present invention, the optical axis of the test lens is made to coincide with the optical axis of the interferometer with reference to the annular flat surface portion (R2 flat surface portion) when the test lens is mounted. The object is to obtain a method and apparatus capable of measurement.

  In the aspect of the wavefront aberration measuring method for measuring the wavefront aberration of the test lens having the annular flat portions on the front and back lens surface peripheries with the interferometer, the present invention provides a front and back ring of the test lens placed on the sample stage. Inclination measurement light is made incident on the flat reference portion of the flat surface portion that is in contact with the lens holder when the lens to be tested is mounted, and is reflected by the reflected light from the lens to be measured. Detecting the tilt amount of the test lens from the interferometer optical axis; adjusting the tilt of the sample stage based on the tilt detection amount and matching the test lens optical axis with the interferometer optical axis; And measuring the wavefront aberration by the interferometer in a state where the optical axes coincide with each other.

  Specifically, the interferometer reflects an interference light source that emits interference fringe measurement light toward the lens to be examined, and the interference fringe measurement light emitted from the interference light source and transmitted through the test lens to the original optical path. Reflecting means having a concave reflecting surface, a cover glass on the reflecting means, interference fringe measurement direct reflected light reflected by the annular flat surface portion of the test lens, and interference reflected by the reflecting means and transmitted through the test lens An interference fringe observation imaging device for observing the interference fringes by making the fringe measurement transmitted reflected light incident, and before the step of detecting the inclination of the lens to be examined, the reflection means of the interferometer and the cover glass are examined. A step of retracting from the optical path of the lens tilt measurement light.

  The present invention can deal with the case where the reflecting means and the cover glass of the interferometer are integrated or can be moved separately. In the case of the integrated type, a step of detecting the tilt from the optical axis of the cover glass interferometer and correcting the tilt of the reflecting means and the cover glass can be included. A step of detecting and correcting tilt from the metering optical axis can be included.

  Alternatively, the diameter of the reflection means and the cover glass of the interferometer is made smaller than the diameter of the tilt measurement light of the lens tilt amount detection device and the interference fringe measurement light of the interferometer, and the reflection means and the cover glass are moved. The step of detecting the tilt amount from the interferometer optical axis of the lens to be tested placed on the sample stage can be executed without doing so.

  In the aspect of the wavefront aberration measuring apparatus for a test lens for measuring the wavefront aberration of an objective lens having an annular flat portion on each of the front and back lens surface peripheral edges by an interferometer, a sample table on which the test lens is placed, Tilt light that causes tilt measurement light to be incident on the mounting reference annular plane portion on the mounting surface side when the lens to be tested is mounted among the annular plane portions on the front and back of the lens to be tested placed on the sample stage. A test lens tilt amount detection device having a detection light source and an imaging device for detecting the reflected light; and an αβ stage for adjusting the tilt of the sample stage. Based on the amount of tilt of the lens, the tilt of the sample stage is adjusted by the αβ stage so that the optical axis of the lens on the sample stage coincides with the optical axis of the interferometer. It is characterized by taking measurements

  Specifically, the interferometer reflects an interference light source that emits interference fringe measurement light toward the lens to be examined, and the interference fringe measurement light emitted from the interference light source and transmitted through the test lens to the original optical path. Reflecting means having a concave reflecting surface, a cover glass on the reflecting means, interference fringe measurement direct reflected light reflected by the annular flat surface portion of the test lens, and interference reflected by the reflecting means and transmitted through the test lens And an interference fringe observation imaging device for observing the interference fringes by making the fringe measurement transmitted reflected light incident thereon. Further, the reflection means of the interferometer and the cover glass are inspected by the inclination detecting device of the lens to be inspected. When detecting the tilt of the lens, a retracting mechanism for retracting from the tilt light detection optical path of the lens tilt detecting device to be detected can be provided.

  In the aspect in which the reflection means of the interferometer and the cover glass are integrated, a through hole through which the reflected light from the cover glass is transmitted can be provided in the sample table.

  The reflection means and the cover glass of the interferometer may be individually movable. At this time, an αβ stage for adjusting the inclination of the cover glass is preferably provided.

  When the diameter of the reflection means and the cover glass of the interferometer is set to be smaller than the diameter of the tilt measurement light of the lens tilt amount detection device and the interference fringe measurement light of the interferometer, the reflection means and the cover glass retracting mechanism Is unnecessary.

  The method and apparatus for measuring the transmitted wavefront aberration of a test lens according to the present invention detects the inclination of the test lens with reference to the annular flat surface portion (R2 flat surface portion) when the test lens is mounted. Since the optical axis is made coincident with the optical axis of the interferometer, and then the transmitted wavefront aberration is measured by the interferometer, various aberrations specific to the lens to be measured can be accurately measured.

  1 to 7 show a first embodiment of a method and apparatus for measuring transmitted wavefront aberration of a test lens according to the present invention, and FIG. 6 shows a light shown as a test lens as a subject of the present invention. An example of the shape of the pickup objective lens L is shown. The objective lens L to be tested includes an annular R1 plane portion and an R2 plane portion that are parallel to each other and are designed to be orthogonal to the optical axis at the periphery of the front and back lens surfaces. The R2 plane portion is a reference surface that is brought into contact with the lens holder of the apparatus when mounted on an actual apparatus (optical pickup) and serves as an optical reference.

  First, the elements of a normal interferometer (transmitted wavefront measuring apparatus) will be described. The interferometer has a collimator lens 12, an interference fringe observation half mirror 13, a reference plane plate 14, a point image observation half mirror 15, a sample stage (in order) on the optical path of a semiconductor laser light source (LD) 11 as an interference light source. An αβXYZ stage) 16 and a concave reflecting mirror 17 having a cover glass 17C are provided.

  An interference fringe observation imaging device 18 and its monitor (interference fringe observation monitor) 18M are arranged on the branch optical path from the interference fringe observation half mirror 13, and on the branch optical path from the point image observation half mirror 15. A point image observation imaging device 19 and a monitor (point image observation monitor) 19M are arranged. The sample stage 16 is used to place the objective lens L to be tested and the like, and can adjust the inclination of the mounting element with respect to the optical axis, the plane position in the plane orthogonal to the optical axis, and the position in the optical axis direction. . Such a stage is well known. Strictly speaking, the placement unit such as the objective lens L to be tested and the adjustment unit (αβ stage and XYZ stage) have different configurations. The αβ stage is a stage that can adjust the tilt with respect to the optical axis, and the XYZ stage is a stage that can adjust the plane position and the optical axis direction position in the optical axis orthogonal plane.

  In the present embodiment, in addition to the above-described elements of a normal interferometer, an inclination measuring laser is directed toward the R2 plane portion of the R1 plane portion and the R2 plane portion of the objective lens L placed on the sample stage 16. A semiconductor laser light source (LD) (tilt light detection light source) 21 for projecting light and an R2 surface point image pickup device 22 for detecting the reflected light are provided. The R2 plane point image capturing device 22 is connected to a monitor (R2 plane point image observation monitor) 22M. In addition, the concave reflecting mirror 17 is not only tilt-adjusted by the αβ stage 17A, but also retracted in the direction of the main optical axis of the interferometer or in the direction perpendicular to the optical axis by the concave mirror retracting stage 17B Is possible. The point that the concave reflecting mirror 17 can be moved in the optical axis direction or the optical axis vertical direction by the concave mirror retracting stage 17B is a configuration that the conventional interferometer does not have.

  Further, as schematically shown in FIG. 7, the sample stage 16 is formed with a circular through hole 16H into which the lens surface of the objective lens L to be tested is dropped and a surrounding R2 plane portion mounting surface. A discontinuous through hole 16R having a diameter larger than that of the R2 plane portion is formed on the mounting surface. The discontinuous through-hole 16R has an effect of allowing the laser light from the semiconductor laser light source 21 to pass through and irradiating the R2 plane portion and allowing the reflected light from the cover glass 17C of the concave reflecting mirror 17 to pass. The cover glass 17C is an optical element corresponding to the light transmission protective layer of the recording medium of the optical pickup device, and the optical performance of the test objective lens L is measured as a composite performance with the cover glass 17C. The concave reflecting mirror 17 can be replaced with a hemispherical mirror as reflecting means having a concave reflecting surface.

  In the present embodiment, the transmission wavefront aberration of the test objective lens is measured in the following steps using the transmission wavefront aberration measurement apparatus for the test objective lens having the above configuration.

Interferometer Reference Point Determination Step As shown in FIG. 1, a corner cube prism 31 is placed on the sample stage 16, and laser light (interference fringe measurement light) is emitted from the semiconductor LD light source 11. Then, the laser beam is reflected by the reference plane plate 14 and enters the interference fringe observation imaging device 18 via the interference fringe observation half mirror 13, and at the same time enters the corner cube prism 31 and returns through the optical path. Since the light is incident on the interference fringe observation imaging device 18 via the interference fringe observation half mirror 13, the interference fringe observation monitor 18M can observe the interference fringes. Then, the inclination of the reference plane plate 14 is adjusted so that the interference fringes become one color, and the point image position on the point image observation monitor 19M at this time is recorded as the reference point I.

R2-plane-side reference point determination step As shown in FIG. 2, an optical parallel 32 is placed on the sample stage 16 instead of the corner cube prism 31, and the point image position of the reflected light by the optical parallel 32 is point image observation. The sample stage 16 is aligned with the reference point I on the monitor 19M.
Adjust. Alternatively, the inclination of the sample stage 16 is adjusted so that the interference fringe observed by the interference fringe observation monitor 18M becomes one color. By this adjustment, the optical parallel 32 plane (the lens mounting surface of the sample stage 16) is orthogonal to the interferometer optical axis.

Next, as shown in FIG. 3, the concave reflecting mirror 17 is retracted from the sample stage 16 (optical parallel 32), and laser light (tilt measurement light) can be irradiated onto the optical parallel 32 by the semiconductor laser light source 21. . When laser light is irradiated from the semiconductor laser light source 21 to the back surface of the optical parallel 32, the reflected light enters the R2 plane point image capturing device 22, and a point image is observed on the R2 plane point image observation monitor 22M. The point image position on the R2 plane point image observation monitor 22M is recorded as the reference point II. This reference point corresponds to an optical parallel 32 (lens mounting surface of the sample stage 16) orthogonal to the interferometer optical axis.

Measurement Lens Tilt Adjustment Step As shown in FIG. 4, with the concave reflecting mirror 17 retracted, the objective lens L to be examined is placed on the sample stage 16 with the R2 plane portion facing downward instead of the optical parallel 32. To do. In this state, the tilt measuring light from the semiconductor laser light source 21 is incident on the R2 plane portion of the objective lens L through the discontinuous through hole 16R of the sample stage 16, and observed by the R2 plane point image observation monitor 22M. The sample stage 16 is adjusted so that the point image overlaps the reference point II. When this adjustment is completed, even if dust is sandwiched between the R2 plane portion of the objective lens L to be tested and the lens mounting surface of the sample stage 16, or a molding burr is generated on the R2 plane portion, The optical axis of the objective lens L coincides with the interferometer optical axis.

As shown in FIG. 5, the concave reflecting mirror 17 is returned to the original observation position, the point image position of the point image observation monitor 19M by the semiconductor LD light source 11 is observed, and the cover glass 17C of the concave reflecting mirror 17 is observed. Is adjusted so that the position of the reflection point image from the reference point I coincides with the reference point I. This adjustment ends the adjustment on the interferometer side.

Transmitted wavefront aberration measurement step The test objective lens L is auto-collimated by the sample stage 16, and transmitted wavefront measurement is performed. That is, when the laser light (interference fringe measurement light) from the semiconductor LD light source 11 is incident on the test objective lens L, the interference fringes that pass through the test objective lens L, are reflected by the concave reflecting mirror 17, and return to the original optical path. The measured transmitted reflected light enters the interference fringe observation imaging device 18, and at the same time, the reflected light reflected by the reference plane plate 14 enters the interference fringe observation imaging device 18. By observing the interference fringes generated by both the lights with the interference fringe observation monitor 18M, the correct wavefront aberration of the objective lens L, that is, the optical axis of the objective lens L to be correctly matched with the optical axis of the interferometer. It is possible to measure wavefront aberration in a state where The method of fringe analysis is well known.

    FIGS. 8 to 12 show a second embodiment of the method and apparatus for measuring the transmitted wavefront aberration of the objective lens L according to the present invention. FIGS. 8, 9, 10, 11 and 12 are respectively shown in FIGS. 1, 2, 3, 4, and 5. In this embodiment, the apparatus configuration of FIGS. 1 to 5 is turned upside down, the R1 plane portion of the objective lens L to be in contact with the lens mounting surface on the sample stage 16, and R2 by the semiconductor laser light source 21. In this embodiment, the flat surface is irradiated without passing through the discontinuous through holes 16R of the sample stage 16. That is, the R2 plane part of the objective lens L to be examined is opened upward when it is placed on the sample stage 16, and the R2 plane part is irradiated with the tilt measuring light from the semiconductor laser light source 21. The The discontinuous through-hole 16R of the sample stage 16 gives the laser light from the semiconductor LD light source 11 to the cover glass 17C and returns the reflected light to the point image observation imaging device 18 when adjusting the inclination detection of the cover glass 17C. (Fig. 12). Other configurations and adjustment measurement steps are the same as those in the first embodiment.

    FIGS. 13 to 18 show a third embodiment of the method and apparatus for measuring the transmitted wavefront aberration of the objective lens L to be tested according to the present invention. In this embodiment, the cover glass 17C of the concave reflecting mirror 17 can be moved and adjusted independently of the reflecting mirror main body portion 17X, and the tilt detection of the cover glass 17C is performed for imaging the semiconductor laser light source 21 and the R2 plane point image. It differs from the first embodiment in that it can be performed by the device 22 (R2 plane point image observation monitor 22M). That is, the cover glass 17C not only moves integrally with the reflector body 17X as shown in FIGS. 13 to 15, but also moves away from the reflector body 17X as shown in FIG. And the inclination can be adjusted independently (it is on the αβ stage).

  In this embodiment, FIGS. 13, 14, 15, 16, and 18 correspond to FIGS. 1, 2, 3, 4, and 5, respectively. FIG. 17 shows a semiconductor laser light source when the cover glass 17C is alone (away from the reflector main body portion 17X) and at the interference measurement position close to the sample table 16 (when only the reflector main body portion 17X is retracted). 21 shows a state in which tilt measurement light is incident on the cover glass 17C by 21 and the reflected light is received by the R2 plane point image pickup device 22. The point image position of the reflected light of the cover glass 17C observed by the R2 surface point image observation monitor 22M is the point image position (reference position II) of the reflected light of the optical parallel 32 on the R2 surface point image observation monitor 22M. The cover glass 17C can be made orthogonal to the optical axis of the interferometer by adjusting so as to coincide with.

    FIGS. 19 to 24 show a fourth embodiment of the method and apparatus for measuring the transmitted wavefront aberration of the objective lens L according to the present invention. FIGS. 19, 20, 21, 22, 23 and 23 are shown in FIGS. Reference numeral 24 corresponds to FIGS. 13, 14, 15, 16, 17, and 18, respectively. In this embodiment, the configuration of the apparatus shown in FIGS. 13 to 18 is turned upside down, the R1 plane portion of the objective lens L to be in contact with the lens mounting surface on the sample stage 16, and R2 by the semiconductor laser light source 21. In this embodiment, the flat surface is irradiated without passing through the discontinuous through holes 16R of the sample stage 16. The relationship between the third and fourth embodiments corresponds to the relationship between the first and second embodiments, and the basic configuration and each adjustment measurement step are the same as those of the third embodiment.

  25 to 29 show a fifth embodiment of the method and apparatus for measuring transmitted wavefront aberration of the objective lens L to be tested according to the present invention. In this embodiment, the diameters of the concave reflecting mirror 17 and the cover glass 17C are made sufficiently smaller than the diameter of the objective lens L to be fixed, the semiconductor laser light source 21 is positioned on the interferometer optical axis, and the semiconductor LD light source 11 is fixed. The cube half mirror 23 is disposed between the sample stage 16 and the semiconductor laser light source 21 on the opposite side, and the R2 plane point image pickup device 22 is disposed on the branch optical axis of the cube half mirror 23. Yes. 25, 26, 27, 28, and 29 correspond to FIGS. 1, 2, 3, 4, and 5, respectively.

In this embodiment, the steps of FIGS. 25 and 26 are the same as the steps of FIGS. On the other hand, in the step of FIG. 27, since the diameters of the concave reflecting mirror 17 and the cover glass 17C are made sufficiently smaller than the objective lens L, the concave reflecting mirror 17 and the cover glass 17C are not retracted from the optical axis. The laser beam (tilt measurement light) from the R2 plane point image pickup device 22 can be irradiated onto the interferometer optical axis. The tilt measurement light is irradiated to the optical parallel 32 arranged perpendicularly to the interferometer optical axis in the previous step through the discontinuous through hole 16R of the sample stage 16, so that the reflection point image is represented by the R2 plane point. The reference point II can be stored in the image observation monitor 22M. The following steps of FIG. 28 and FIG. 29 are the same as the steps of FIG. 4 and FIG.

1 is an optical layout diagram showing a first embodiment of a method and apparatus for measuring transmitted wavefront aberration of a lens to be tested according to the present invention. It is an optical layout diagram of the next step of the first embodiment. It is an optical layout diagram of the next step of the first embodiment. It is an optical layout diagram of the next step of the first embodiment. It is an optical layout diagram of the next step of the first embodiment. It is a longitudinal cross-sectional view which shows the example of a shape of the test lens which the transmission wavefront aberration measuring method and apparatus of the test lens by this invention make object. It is a top view which shows the example of a shape of the sample stand which mounts the said test lens. It is an optical arrangement | positioning figure which shows 2nd embodiment of the transmitted wavefront aberration measuring method and apparatus of the test lens by this invention. It is an optical layout diagram of the next step of the second embodiment. It is an optical layout diagram of the next step of the second embodiment. It is an optical layout diagram of the next step of the second embodiment. It is an optical layout diagram of the next step of the second embodiment. FIG. 6 is an optical layout diagram showing a third embodiment of a method and apparatus for measuring transmitted wavefront aberration of a test lens according to the present invention. It is an optical layout diagram of the next step of the third embodiment. It is an optical layout diagram of the next step of the third embodiment. It is an optical layout diagram of the next step of the third embodiment. It is an optical layout diagram of the next step of the third embodiment. It is an optical layout diagram of the next step of the third embodiment. FIG. 7 is an optical layout diagram showing a fourth embodiment of a method and apparatus for measuring transmitted wavefront aberration of a lens to be tested according to the present invention. It is an optical layout diagram of the next step of the fourth embodiment. It is an optical layout diagram of the next step of the fourth embodiment. It is an optical layout diagram of the next step of the fourth embodiment. It is an optical layout diagram of the next step of the fourth embodiment. It is an optical layout diagram of the next step of the fourth embodiment. FIG. 6 is an optical layout diagram showing a fifth embodiment of a method and apparatus for measuring transmitted wavefront aberration of a test lens according to the present invention. It is an optical layout diagram of the next step of the fifth embodiment. It is an optical layout diagram of the next step of the fifth embodiment. It is an optical layout diagram of the next step of the fifth embodiment. It is an optical layout diagram of the next step of the fifth embodiment.

Explanation of symbols

L Objective lens (test lens)
R1 annular plane part R2 mounting reference annular plane part 11 semiconductor LD light source (for interference fringe observation)
12 Collimator lens 13 Interference fringe observation half mirror 14 Reference plane plate 15 Point image observation half mirror 16 Sample stage (αβXYZ stage)
17 Concave mirror 17C Cover glass 17A αβ stage 17B Concave mirror retracting stage 17X Reflector main body 18 Interference fringe observation imaging device 18M Interference fringe observation monitor 19 Point image observation imaging device 19M Point image observation monitor 21 Semiconductor laser light source (tilt detection) for)
22 R2 surface image capturing device cube half mirror 23
31 Corner cube prism 32 Optical parallel

Claims (12)

In the wavefront aberration measuring method for measuring the wavefront aberration of the test lens having the annular flat portions on the front and back lens surface peripheral edges with an interferometer,
Inclination measurement light is incident on the mounting reference annular flat surface portion that comes into contact with the lens holder when mounting the test lens, out of the annular flat surface portions of the front and back surfaces of the test lens placed on the sample table, Detecting the amount of inclination of the test lens from the optical axis of the interferometer from the reflected light of the test light from the test lens;
Adjusting the tilt of the sample stage based on the tilt detection amount, and aligning the optical axis of the lens to be tested with the optical axis of the interferometer;
Performing wavefront aberration measurement with the interferometer in the optical axis coincidence state;
A method for measuring a transmitted wavefront aberration of a lens to be measured, comprising: 2. The transmitted wavefront aberration measurement method for a test lens according to claim 1, wherein the interferometer includes an interference light source that emits interference fringe measurement light toward the test lens, and the test light emitted from the interference light source. Reflecting means having a concave reflecting surface for reflecting the transmitted interference fringe measuring light to the original optical path, a cover glass on the reflecting means, the interference fringe measuring directly reflected light reflected by the annular plane portion of the lens to be tested, and the above An interference fringe observation imaging device for observing the interference fringes by entering the interference fringe measurement transmission reflected light reflected by the reflecting means and transmitted through the test lens;
A method for measuring a transmitted wavefront aberration of a test lens, comprising the step of retracting the reflecting means and the cover glass of the interferometer from the optical path of the tilt measurement light of the test lens before the step of detecting the tilt of the test lens. 3. The method for measuring transmitted wavefront aberration of a test lens according to claim 2, wherein the reflecting means of the interferometer and the cover glass are integrated, and an inclination is detected from an optical axis of the interferometer of the cover glass to detect the inclination of the reflecting means and the cover glass. A method for measuring a transmitted wavefront aberration of a lens to be examined, including the step of correcting 3. The method of measuring transmitted wavefront aberration of a test lens according to claim 2, wherein the reflecting means of the interferometer and the cover glass are individually movable, and further, the inclination is detected and corrected from the optical axis of the interferometer of the cover glass. A method for measuring a transmitted wavefront aberration of a lens to be tested including a step. 2. The transmitted wavefront aberration measuring apparatus for a test lens according to claim 1, wherein the reflecting means of the interferometer and the diameter of the cover glass are the diameter of the tilt measuring light of the tilt amount detecting device of the test lens and the interference fringe measurement of the interferometer. Transmitted wavefront aberration that is smaller than the diameter of the light and that performs the above-described step of detecting the amount of inclination of the test lens placed on the sample stage from the interferometer optical axis without moving the reflecting means and the cover glass Measuring method. In the wavefront aberration measuring device for the lens to be measured for measuring the wavefront aberration of the objective lens having the annular flat portions on the front and back lens surface peripheral edges by an interferometer,
A sample stage on which the test lens is placed;
Inclined light for inclining measurement light incident on the mounting reference annular flat surface portion on the mounting surface side when mounting the test lens among the front and back annular flat surface portions of the test lens mounted on the sample stage. A tilt amount detection device for a lens to be tested, which includes a detection light source and an imaging device for detecting the reflected light;
An αβ stage for adjusting the inclination of the sample stage;
With
Based on the tilt amount of the test lens by the tilt amount detector of the test lens, the tilt of the sample stage is adjusted by the αβ stage so that the test lens optical axis on the sample stage matches the interferometer optical axis, An apparatus for measuring a transmitted wavefront aberration of a lens to be measured, wherein wavefront aberration is measured by the interferometer in a state where the optical axes coincide with each other. 7. The apparatus for measuring transmitted wavefront aberration of a test lens according to claim 6, wherein the interferometer includes an interference light source that emits interference fringe measurement light toward the test lens, and the test light emitted from the interference light source. Reflecting means having a concave reflecting surface for reflecting the transmitted interference fringe measuring light to the original optical path, a cover glass on the reflecting means, the interference fringe measuring directly reflected light reflected by the annular plane portion of the lens to be tested, and the above An interference fringe observation imaging device that observes the interference fringes by making the interference fringe measurement transmitted reflected light reflected by the reflecting means and transmitted through the test lens, and further, the reflecting means and the cover glass of the interferometer, An apparatus for measuring transmitted wavefront aberration of a test lens, comprising: a retraction mechanism for retreating from the tilt light detection optical path of the test lens tilt detection device when the tilt detection device detects the tilt of the test lens. 7. A transmission wavefront aberration measuring apparatus for a test lens according to claim 6, wherein the reflecting means of the interferometer and the cover glass are integrated. 9. The transmitted wavefront aberration measuring apparatus for a test lens according to claim 8, wherein the sample stage includes a through hole through which reflected light from the cover glass is transmitted. 8. The transmitted wavefront aberration measuring apparatus for a test lens according to claim 7, wherein the reflecting means and the cover glass of the interferometer are individually movable. The transmitted wavefront aberration measuring apparatus for a test lens according to claim 10, further comprising an αβ stage for adjusting the inclination of the cover glass. 12. The transmitted wavefront aberration measuring apparatus for a test lens according to claim 6, wherein the reflecting means of the interferometer and the diameter of the cover glass are the diameters of the tilt measuring light of the tilt amount detecting device of the test lens. And a transmitted wavefront aberration measuring apparatus set to a diameter smaller than the diameter of the interference fringe measurement light of the interferometer.

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