JP2008304200A - Method for adjusting height position of eccentricity measuring head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for adjusting the height position of an eccentricity measuring head and also easily and highly accurately adjusting the height position of a second eccentricity measuring head arranged below a base at which an optical element to be inspected is mounted and held in an eccentric amount measuring apparatus provided with two eccentricity measuring heads. <P>SOLUTION: An original position O<SB>2</SB>of the second measuring head 10B is computed on the basis of: the amount ΔH<SB>1</SB>of positional changes of a first measuring head 10A from an initial position O<SB>P1</SB>when the focal planes of the first and second measuring heads 10A and 10B are superposed on each other to an original position O<SB>1</SB>when the foal plane of the first measuring head 10A is superposed on a paraxial region of a lens surface 51a; an initial position O<SB>P2</SB>of the second measuring head 10B; and the overall length D<SB>L</SB>of a lens body 5. The height position O<SB>m2</SB>of the second measuring head 10B at the time of measurement is computed on the basis of the origin position O<SB>2</SB>, and a design value D<SB>R</SB>of the distance from the paraxial center C<SB>3</SB>of curvature of a lens surface 52a to a lens surface 52b so as to move the second measuring head 10B to the height position O<SB>m2</SB>. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention provides a first eccentricity measuring head positioned on one side (for example, above) of the base and the other side of the base (on the upper side) with the base on which the test optical element is placed and held ( For example, in the eccentricity measuring device arranged so that the second eccentricity measuring head located in the lower side is opposed to each other, the height position of the second eccentricity measuring head at the time of measurement is adjusted. The present invention relates to a method for adjusting the height position of an eccentricity measuring head.

  As a conventional eccentricity measuring device, one having only one eccentricity measuring head (see, for example, Patent Document 1) and two eccentricity measuring heads arranged to face each other as described above. (For example, see Patent Document 2), both of which generally employ a measurement technique called an autocollimation method.

  In the autocollimation method, the height is adjusted so that the paraxial center of curvature of the test surface of the test optical element is located at the focal plane of the eccentricity measuring head, and then the test surface is rotated about a predetermined rotation axis. While rotating, an index image of a predetermined shape is formed on the focal plane. This index image is relayed through the test surface and imaged on the imaging surface that is conjugated with the focal plane. At this time, if the test surface is eccentric, Since the index image moves so as to draw a circular trajectory as the surface rotates, the eccentricity of the surface to be measured can be obtained by measuring the radius of this circle.

  In an eccentricity measuring device having two eccentricity measuring heads, measurement is usually performed using an eccentricity measuring head (hereinafter referred to as “upper measurement head”) disposed above, Test surface that cannot be measured by the upper measurement head (when installed on the base, the paraxial curvature center is located at a position away from the upper measurement head, so the paraxial curvature center is located at the focal plane of the upper measurement head. The test surface that cannot be positioned has an advantage that it can be measured using an eccentric measurement head (hereinafter referred to as “lower measurement head”) disposed below.

JP 2007-17431 A JP-A-2005-55202

  However, the eccentricity measuring apparatus having two eccentricity measuring heads adjusts the height position of the lower measuring head (the paraxial center of curvature of the test surface is positioned on the focal plane of the lower measuring head). Adjustment) is difficult.

  The reason for this is that in the case of the lower measurement head, since the base is interposed between the optical head and the optical element to be measured, it is difficult to actually measure the distance to the optical element to be measured, which is a reference for height adjustment. It is difficult to set a position (hereinafter referred to as “origin position”).

  In the case of the upper measuring head, since the base is not interposed between the optical head and the test optical element, for example, the uppermost lens surface of the test optical element installed on the base (hereinafter referred to as the “uppermost lens surface”). The upper measuring head is moved to a height position where the paraxial region of the upper measuring head and the focal plane of the upper measuring head overlap each other, and the height position at this time is set as the origin position of the upper measuring head. It becomes possible. Such a setting method can be performed while observing the index image reflected from the uppermost lens surface and formed on the imaging surface of the upper measurement head, and the setting accuracy is high.

  Applying such a setting method to the lower measurement head, for example, a paraxial region of a lens surface (hereinafter referred to as “lowermost lens surface”) positioned at the lowermost position in the optical element to be tested installed on the base; Even if the lower measurement head is moved to a height position where the focal planes of the lower measurement head overlap with each other, the base may not be an obstacle. For this reason, conventionally, a method has been adopted in which the distance between the lowermost lens surface and the lower measurement head is measured using another measurement means, and the origin position of the lower measurement head is set based on the measured value. However, such a method has a complicated procedure, and it is difficult to adjust the height with high accuracy.

  The present invention has been made in view of such circumstances, and in an eccentricity measuring apparatus having two eccentricity measuring heads, the other of the bases on which the optical element to be tested is placed and held. It is an object to provide a method for adjusting the height position of an eccentricity measuring head capable of easily and accurately adjusting the height position during measurement of the second eccentricity measuring head arranged on the side. And

The method of adjusting the height position of the eccentricity measuring head according to the present invention includes a base on which a test optical element having a plurality of lens surfaces is placed and held on one side of the base. The first eccentricity measuring head located and the second eccentricity measuring head located on the other side of the base are arranged to face each other,
The first eccentricity measuring head and the second eccentricity measuring head transmit light from a light source to the test optical element placed and held on the base via an index of a predetermined shape. Irradiation optical system that irradiates and forms an image of the index on the focal plane, and the reflected light or transmitted light from the lens surface whose paraxial curvature center is located on the focal plane is guided onto the imaging surface. In an eccentricity measuring device each comprising an imaging optical system that forms an image of the index formed by transmitted light on an imaging surface,
The second paraxial curvature center of a predetermined lens surface to be measured by the second eccentricity measuring head and the focal plane of the second eccentricity measuring head overlap each other. A method for adjusting the height position of the eccentricity measuring head, wherein the eccentricity measuring head is moved to a height position during measurement,
In a state where the test optical element is not placed and held on the base, the focal plane of the first eccentricity measuring head and the focal plane of the second eccentricity measuring head are mutually The relative height adjustments of the first and second eccentricity measuring heads are performed so as to overlap, and the heights of the first and second eccentricity measuring heads at the time when the height adjustment is completed. Both head initial position recording steps for recording the position as the first and second initial positions respectively;
In a state where the test optical element is placed and held on the base, the focal plane of the first decentering measurement head is a paraxial region of a predetermined first lens surface of the test optical element. The height of the first eccentricity measuring head is adjusted so as to overlap, and the height position of the first eccentricity measuring head when the height adjustment is completed is recorded as the first origin position. A first head origin position recording step;
The difference value of the distance between the first initial position of the first eccentricity measuring head and the first origin position, and the distance from the predetermined second lens surface of the optical element to be tested to the first lens surface. Based on a design value and the second initial position of the second eccentricity measuring head, the focal plane of the second eccentricity measuring head overlaps with a paraxial region of the second lens surface. A second head origin position calculation recording step of calculating a height position of the second eccentricity measuring head and recording this as a second origin position;
Based on the second origin position of the second eccentricity measuring head and the design value of the distance from the paraxial center of curvature of the lens surface to be examined to the second lens surface, the second eccentricity The measurement head height position of the measurement head is calculated, and the second head measurement position adjustment step for moving the second eccentric measurement head to the calculated measurement height position is performed in this order. It is characterized by that.

  In the method for adjusting the height position of the eccentricity measuring head according to the present invention, the relative height adjustment of the first and second eccentricity measuring heads in the initial position recording step of both the heads is performed by the first method. An image of the index imaged on the focal plane of the first eccentricity measuring head by the eccentricity measuring head is transmitted through the imaging optical system of the second eccentricity measuring head. The image can be formed on the imaging surface of the eccentricity measuring head 2.

  In addition, the height adjustment of the first eccentricity measuring head in the first head origin position recording step is performed by irradiating the first lens surface from the first eccentricity measuring head. The reflected image returning to the first eccentricity measuring head can be performed so that the index image is formed on the imaging surface of the first eccentricity measuring head.

  In the present invention, it is mainly assumed that the first eccentricity measuring head is disposed above the base and the second eccentricity measuring head is disposed below the base. It is not limited to such an embodiment. A mode in which the first eccentricity measuring head is arranged below the base and the second eccentricity measuring head is arranged above the base, and the first and second eccentricity measuring heads are based on A mode in which the base is arranged on both the left and right sides of the base is also included. In addition, the height adjustment in the aspect in which the first and second eccentricity measuring heads are respectively arranged on the left and right sides of the base means position adjustment in the left-right direction.

  According to the height position adjusting method for the eccentricity measuring head according to the present invention, the origin position (second origin position) that serves as a reference for height position adjustment in the second eccentricity measuring head is set to the first deviation measuring position. Since it can be calculated based on the amount of movement of the center measurement head, the base becomes an obstacle, and the focal plane of the second eccentric measurement head cannot be adjusted to such an origin position. However, it is possible to easily and accurately adjust the height position during measurement of the second eccentricity measuring head.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a method for adjusting the height position of an eccentricity measuring head according to the present invention will be described in detail with reference to the drawings.
First, the configuration of an eccentricity measuring device to which the present invention is applied will be described. FIG. 3 is a schematic configuration diagram of an eccentricity measuring apparatus to which the present invention is applied.

  A decentering amount measuring apparatus 1 shown in FIG. 3 measures the decentering amount of each lens surface of a lens body 5 as a test optical element by applying an autocollimation method. Head (hereinafter referred to as “first measurement head”) 10A and second eccentricity measurement head (hereinafter referred to as “second measurement head”) 10B, and a base 20 that rotatably holds the lens body 5; And an analysis calculation unit 30 that performs various calculations for calculating the amount of eccentricity, and a Z-axis stage 40 that holds the first measurement head 10A and the second measurement head 10B movably in the vertical direction in the figure. Become.

The first measurement head 10 </ b> A and the second measurement head 10 </ b> B are positioned above the base 20 and the second measurement head 10 </ b> B is at the base 20 so that they face each other across the base 20. Are arranged below each. The first measurement head 10A and the second measurement head 10B include a light source 11 that outputs a light beam applied to the lens body 5 and a cross-shaped slit (hereinafter referred to as “an index”) that allows the light beam output from the light source 11 to pass therethrough. Reticle plate 12 having a "reticle"), a beam splitter 13 for reflecting the light beam from the reticle plate 12 at a right angle, a collimator lens 14 for making the incident light beam a parallel light beam, and the parallel light beam for each light convergence point. An objective lens 15 that converges on P ₁ and P ₂ and an imaging camera 17 equipped with an imaging element 16 such as a CCD or CMOS are provided.

In the present embodiment, the reticle plate 12, the beam splitter 13, the collimator lens 14, the objective lens 15 and the like constitute an irradiation optical system. The objective lens 15, the collimator lens 14, The beam splitter 13 and the like constitute an imaging optical system. Further, the light converging point _{P 1,} the first match (the objective lens 15) the focus of the measurement head 10A, the light converging point _{P 2,} the above second measuring head 10B (the objective lens 15) focus The first measurement head 10A and the second measurement head 10B form the image of the reticle on each focal plane (surface on which the light convergence points P ₁ and P ₂ are respectively located; not shown). It is configured to be able to.

On the other hand, the lens body 5 is formed by holding two lenses 51 and 52 in a lens barrel 53. Furthermore, each lens surface 51a of the object surface, 51b, 52a, among the 52 b, for the lens surface 52a located third from the top in the figure, since its paraxial curvature center _{C 3} is located considerably below, in a state where the lens body 5 is installed as shown in FIG. 3, it can not be allowed to position the paraxial curvature center C ₃ of the focal plane on the lens surface 52a of the first measurement head 10A. Therefore, the amount of eccentricity of the lens surface 52a is measured using the second measurement head 10B. However, the length in the height direction of the base 20 is configured to be longer than the focal length of the second measurement head 10B. For this reason, in the state where the lens body 5 is installed on the base 20, the second measurement is performed. if you try to move the second measuring head 10B so as to position the paraxial curvature center C ₃ of the lens surface 52a on the focal plane of the head 10B, base 20 is prevented Deki an obstacle.

The base 20 includes a mounting member 21 on which the lens body 5 is mounted, and an XY axis stage 22 and a rotary stage 23 that support the mounting member 21. Supported by the Z-axis stage 40. The XY axis stage 22 adjusts the position of the optical axis B of the lens body 5 placed on the placement member 21 and the optical axes Z ₁ and Z _{2 of} the first measurement head 10A and the second measurement head 10B. The lens body 5 mounted on the mounting member 21 is used in the case of the in-plane substantially orthogonal to the optical axes Z ₁ and Z _{2 of} the first measurement head 10A and the second measurement head 10B. It is comprised so that it can move in. Further, the rotary stage 23 is configured to be able to rotate the lens body 5 placed on the placement member 21 around the illustrated rotation axis A. Further, the XY axis stage 22 and the rotary stage 23 have a window portion 25 for allowing the lens body 5 placed on the placement member 21 to be observed from below (the second measurement head 10B side) in the figure. Is provided.

  The mounting member 21 may be a cylindrical member that supports the lens body 5 at the upper end surface edge, but Japanese Patent Application No. 2006 already disclosed to the Patent Office by the applicant of the present application. A chuck mechanism composed of a V block and a rotating disk as shown in FIG. 3 of the specification of 157198 (hereinafter referred to as “Patent Document 3”) may be used.

  The analysis operation unit 30 performs analysis of each image captured at the time of measurement, an analysis device 31 as an analysis unit including a computer, an image display device 32 that displays an analysis result, each image, and the like, An input device 33 for performing various inputs to the analysis device 31 is provided.

The Z-axis stage 40 is provided with a base 41, a guide part 42 standing on the base part 41, and movable along the guide part 42 in the vertical direction in the figure. It comprises movable parts 43A and 43B for holding the second measuring head 10B. The Z-axis stage 40 has the lens surfaces 51a, 51b, 52a, 52b on the focal plane of the first measurement head 10A or the second measurement head 10B when measuring the amount of eccentricity of the lens body 5. The paraxial curvature center of the lens surface to be measured is located (for example, when measuring the amount of eccentricity of the lens surface 52a, the paraxial curvature center on the focal plane of the second measuring head 10B). C ₃ as is located), the height position of the first measurement head 10A and the second measuring head 10B (the optical axis _Z 1 of the first measurement head 10A and the second measuring head 10B, _{Z 2} direction position) It comes to adjust.

In measuring the eccentricity, the optical axes Z ₁ and Z _{2 of} the first measurement head 10A and the second measurement head 10B, the optical axis B of the lens body 5, and the base 20 (rotation) It is preferable to adjust the rotation axis A of the stage 23 so that they coincide with each other, but measurement is possible even when they do not coincide with each other. The measurement technique used when the axes do not match is described in detail in the above-mentioned Patent Document 2.

  Next, a method for adjusting the height position of the eccentricity measuring head according to an embodiment of the present invention will be described. FIG. 1 is a schematic diagram showing an outline of a height position adjusting method for an eccentricity measuring head according to an embodiment of the present invention, and FIG. 2 is a flowchart showing the procedure thereof.

The optical axes Z ₁ and Z _{2 of} the first measurement head 10A and the second measurement head 10B, and the optical axis B of the lens body 5, which are performed when the lens body 5 is installed on the base 20, respectively. The description of the positional adjustment between the rotation axes A of the base 20 is omitted. In the following description, the height position adjustment of the second measurement head 10B in the case where the lens surface 52a is the test lens surface and the amount of decentering is measured using the second measurement head 10B will be described as an example. To do.

  <1> In a state where the lens body 5 is not placed and held on the base 20 (a state shown on the left side of FIG. 1), the focal plane of the first measurement head 10A and the focal plane of the second measurement head 10B are mutually The relative height adjustment of the first and second measurement heads 10A and 10B is performed so as to overlap, and the height positions of the first and second measurement heads 10A and 10B at the time when the height adjustment is completed are Recording is performed as respective initial positions (first initial position and second initial position) (both head initial position recording step).

Specifically, first, the first measurement head 10A is lowered to the lowest point (step S1 in FIG. 2), and the height position of the first measurement head 10A at this time is set to its initial position (first initial position) O. Recorded as _P1 (step S2 in FIG. 2). Next, the height of the second measurement head 10B is adjusted so that the focal planes of the first and second measurement heads 10A and 10B overlap each other (step S3 in FIG. 2), and the height of the second measurement head 10B at this time is adjusted. The position is recorded as its initial position (second initial position) _OP2 (step S4 in FIG. 2).

Note that the height adjustment of the second measurement head 10B with respect to the first measurement head 10A installed at the first initial position _OP1 is performed by using the second measurement for the reticle image formed on the focal plane by the first measurement head 10A. Observation can be performed through the head 10B, and the second measurement head 10B can be moved so that the reticle image is formed on the imaging surface of the second measurement head 10B.

<2> Next, in a state where the lens body 5 is placed and held on the base 20 (a state shown on the right side of FIG. 1), the focal plane of the first measurement head 10A is the first lens surface of the lens body 5 ( In the present embodiment, the height of the first measurement head 10A is adjusted so as to overlap with the paraxial region of the lens surface 51a) (hereinafter sometimes referred to as “the surface of the lens body 5”), and this height adjustment is performed. Is recorded as the origin position (first origin position) O ₁ (first head origin position recording step).

Specifically, after the lens body 5 is placed and held on the base 20 (step S5 in FIG. 2), the total length D _L (see FIG. 1) of the lens body 5 is calculated from the design value (step S6 in FIG. 2). ). Then, the first measurement head 10A is moved so that its focal plane is aligned with the surface of the lens body 5, and the height position of the first measurement head 10A at this time is recorded as the origin position O ₁ (step in FIG. 2). S7).

  The height adjustment of the first measurement head 10A at this time can be performed as follows. First, the measurement light beam is irradiated from the first measurement head 10A to the lens surface 51a, and the reflected light from the lens surface 51a is captured by the first measurement head 10A. Next, the height of the first measurement head 10A is adjusted while observing the state of the image captured by the imaging camera 17 of the first measurement head 10A. When the focal plane of the first measurement head 10A overlaps the paraxial region of the lens surface 51a, the reticle image brighter and larger than the reticle image normally observed on the imaging surface of the first measurement head 10A by the reflected light from the lens surface 51a. Since an image that is unnecessary during measurement is formed, the height position of the first measurement head 10A can be adjusted so that the reticle image is observed.

<3> Next, in the initial position O _P1 and the origin position difference value of the distance between O _1, the predetermined second lens surface of the lens body 5 (embodiment of the first measuring head 10A, a lens surface 52b design value of the distance to the lens surface 51a of) (in this embodiment, coincides with the total length _{D L} of the lens body 5), and on the basis of the initial position _{O P2} of the second measuring head 10B, the second measuring head 10B The height position of the second measuring head 10B when the focal plane overlaps the paraxial region of the lens surface 52b (hereinafter sometimes referred to as “the back surface of the lens body 5”) is calculated, and this is calculated for the second measuring head 10B. Recording is performed as an origin position (second origin position) O ₂ (second head origin position calculation recording step).

Specifically, first, the difference value of the distance and the initial position _{O P1} of the first measuring head 10A as an origin position _{O 1,} i.e., the position change of the first measurement head 10A from the initial position _{O P1} to the origin position _{O 1} the amount _{ΔH 1 (= O 1 -O P1} ) was calculated (step S8 in FIG. 2), then the change in position [Delta] H _1, the total length of the initial position _{O P2,} the lens body 5 of the second measuring head 10B _{D L} the basis, calculates the origin position _O 2 of the second measuring head _{10B (= O P1 + ΔH 1} -D L) ( step S9 in FIG. 2).

<4> Next, the origin position _{O 2} of the second measuring head 10B, (in the present embodiment, the lens surface 52a) subject lens surface design value D of the distance from the paraxial curvature center _{C 3} to the lens surface 52b _{Based on R} (see FIG. 1), the measurement height position O _m2 (= O ₂ −D _R ) of the second measurement head 10B is calculated, and the second measurement head 10B is calculated at the calculated measurement height position. (Step S10 in FIG. 2; second head measurement position adjustment step).

  With the above procedure, the height position adjustment of the second measurement head 10B when the lens surface 52a is used as the test surface is completed. Hereinafter, the eccentricity of the lens surface 52a is measured using the second measurement head 10B. Done. The measurement procedure is described in detail in the above-mentioned Patent Document 3, and the description is omitted.

According to the height adjustment method of the eccentricity measuring head according to the present embodiment, the origin position O ₂ of the second measuring head 10B, be calculated based on the amount of movement of the first measuring head 10A Therefore, even when the base 20 becomes an obstacle and the focal plane of the second measurement head 10B cannot be aligned with the origin position O ₂ , the height position at the time of measurement of the second measurement head 10B. Adjustment can be performed easily and with high accuracy.

  The eccentricity measuring device of the present invention is not limited to the above embodiment, and various modifications can be made.

  For example, in the above-described embodiment, a cross-shaped reticle is used as an index. However, instead of this, another shape such as a pinhole can be used as an index.

In the above embodiment, the first lens surface to use as a reflective surface when obtaining the origin position O ₁ of the first measuring head 10A and the lens surface 51a, when determining the origin position O ₂ of the second measuring head 10B The lens surface 52b is used as a reference for the second lens surface. However, the first lens surface is a surface other than the lens surface 51a (for example, the lens surface 51b), or the second lens surface is the lens surface 52b. Other surfaces (for example, the lens surface 52a) may be used.

The schematic diagram which shows the outline | summary of the height position adjustment method which concerns on one Embodiment. The flowchart which shows the procedure of the height position adjustment method which concerns on one Embodiment. Schematic configuration diagram of an eccentricity measuring device to which the present invention is applied

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Eccentricity measuring apparatus 5 Lens body (test optical element)
10A First eccentricity measuring head (first measuring head)
10B Second eccentric measurement head (second measurement head)
DESCRIPTION OF SYMBOLS 11 Light source 12 Reticle plate 13 Beam splitter 14 Collimator lens 15 Objective lens 16 Imaging element 17 Imaging camera 20 Base 21 Mounting member 22 XY axis stage 23 Rotation stage 24 Support part 25 Window part 30 Analytical calculation part 31 Analysis apparatus 32 Image display Device 33 Input device 40 Z-axis stage 41 Base portion 42 Guide portion 43A, 43B Movable portion 51, 52 Lens 51a, 51b, 52a, 52b Lens surface 53 Lens barrel _OP1 initial position (first initial position)
O ₁ origin position (first origin position)
_OP2 initial position (second initial position)
O ₂ origin position (second origin position)
_Om2 measurement height position P ₁ , P ₂ Light convergence point Z ₁ , Z ₂ , B Optical axis A Rotation axis C ₃ Paraxial center of curvature

Claims (3)

A first eccentricity measuring head located on one side of the base, with the base on which the optical element to be tested having a plurality of lens surfaces is placed and held, and the other of the base And the second eccentricity measuring head located on the side of the
The first eccentricity measuring head and the second eccentricity measuring head transmit light from a light source to the test optical element placed and held on the base via an index of a predetermined shape. Irradiation optical system that irradiates and forms an image of the index on the focal plane, and the reflected light or transmitted light from the lens surface whose paraxial curvature center is located on the focal plane is guided onto the imaging surface. In an eccentricity measuring device each comprising an imaging optical system that forms an image of the index formed by transmitted light on an imaging surface,
The second paraxial curvature center of a predetermined lens surface to be measured by the second eccentricity measuring head and the focal plane of the second eccentricity measuring head overlap each other. A method for adjusting the height position of the eccentricity measuring head, wherein the eccentricity measuring head is moved to a height position during measurement,
In a state where the test optical element is not placed and held on the base, the focal plane of the first eccentricity measuring head and the focal plane of the second eccentricity measuring head are mutually The relative height adjustments of the first and second eccentricity measuring heads are performed so as to overlap, and the heights of the first and second eccentricity measuring heads at the time when the height adjustment is completed. Both head initial position recording steps for recording the position as the first and second initial positions respectively;
In a state where the test optical element is placed and held on the base, the focal plane of the first decentering measurement head is a paraxial region of a predetermined first lens surface of the test optical element. The height of the first eccentricity measuring head is adjusted so as to overlap, and the height position of the first eccentricity measuring head when the height adjustment is completed is recorded as the first origin position. A first head origin position recording step;
The difference value of the distance between the first initial position of the first eccentricity measuring head and the first origin position, and the distance from the predetermined second lens surface of the optical element to be tested to the first lens surface. Based on a design value and the second initial position of the second eccentricity measuring head, the focal plane of the second eccentricity measuring head overlaps with a paraxial region of the second lens surface. A second head origin position calculation recording step of calculating a height position of the second eccentricity measuring head and recording this as a second origin position;
Based on the second origin position of the second eccentricity measuring head and the design value of the distance from the paraxial center of curvature of the lens surface to be examined to the second lens surface, the second eccentricity A second head measurement position adjustment step of calculating the measurement height position of the measurement head and moving the second eccentricity measurement head to the calculated measurement height position;
A method for adjusting the height position of the eccentricity measuring head, characterized in that:   The relative height adjustment of the first and second eccentricity measuring heads in the both head initial position recording steps is performed by the first eccentricity measuring head using the first eccentricity measuring head. The index image formed on the focal plane is formed on the imaging surface of the second eccentricity measuring head via the imaging optical system of the second eccentricity measuring head. The method for adjusting the height position of the eccentricity measuring head according to claim 1, wherein the method is performed as described above. The height adjustment of the first eccentricity measuring head in the first head origin position recording step is performed by irradiating the first lens surface from the first eccentricity measuring head to the first lens surface from the first lens surface. 2. The method according to claim 1, wherein the index image is formed on the imaging surface of the first eccentricity measuring head by reflected light returning to the first eccentricity measuring head. 3. A method for adjusting the height position of the eccentricity measuring head according to 2.

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