JP3314525B2 - Wavefront splitting element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wavefront splitting element used for measuring the optical rotation angle of a rotatory substance such as a sucrose solution or quartz.

[0002]

2. Description of the Related Art FIG. 1 shows the principle of measuring the angle of rotation of a conventional polarimeter. First, the polarizer P and the analyzer N are arranged in a crossed Nicols arrangement (FIG. 1 (a)). Then, the optically rotating substance S to be measured is inserted between them, and the analyzer is rotated again to a position where the analyzer becomes a dark field (FIG. 1 (a)). FIG. 1 (b)).

The rotation angle α of the analyzer at this time is the rotation angle due to S.

[0004]

However, the polarimeter according to the conventional method has a movable part, so that the life of the apparatus is short. When the analyzer repeats the rotational movement, wear occurs, leading to a decrease in mechanical accuracy and ultimately to failure. Mechanical durability determined the life of the device.

In the conventional method, the extinction position must be accurately measured. However, when the extinction ratio of the polarizer and the analyzer is poor, the output light intensity does not change so much at any rotation angle. It is difficult to detect.

On the other hand, when the extinction ratio of the polarizer or the analyzer is good, the output light intensity changes abruptly near the extinction position, and changes by two to four digits depending on the extinction ratio. However, since linearity between light intensity and output current cannot be secured,
It is extremely difficult for an ordinary photoelectric detector to follow such a rapid change in intensity.

All the drawbacks of the conventional polarimeter stem from the operating principle of searching for the extinction position. However, in the present invention, by using a wavefront splitting element, by a completely different measurement principle, it does not include a movable part causing a failure, does not depend on the extinction ratio of a polarizer and an analyzer, and has a high-performance photoelectric detection. It enables high-precision measurement of the angle of rotation that does not require an instrument.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention comprises two elements of a phaseless polarizing beam splitter and a polarizer, and transmits or reflects P-polarized light, transmitted light or reflected light of a first beam splitter. The reflected S-polarized light is arranged so as to be the incident S-polarized light and the incident P-polarized light of the second beam splitter, respectively, and the polarizer is disposed on the transmission or reflection side of the second beam splitter so that the transmission axis is 4 from P-polarized light or S-polarized light.
Provided is a wavefront splitting element, which is arranged so as to be rotated by 5 °.

Further, the first beam splitter, which is a phaseless and non-polarized first beam splitter, is composed of three elements of a non-phase non-polarizing beam splitter, a polarizing beam splitter, and a polarizer. The second polarizing beam splitter is arranged so as to be incident P-polarized light and incident S-polarized light, and the polarizer is disposed on the transmission or reflection side of the first beam splitter such that the transmission axis is 45 degrees away from the P-polarized light or the S-polarized light.
Provided is a wavefront splitting element characterized in that the wavefront splitting element is arranged so as to be rotated by a degree.

The beam splitter and the like used in the device of the present invention are as follows. That is, P-polarized light transmittance is Tp, P-polarized light reflectance is Rp, S-polarized light transmittance is Ts,
When the S-polarized light reflectance is Rs, the phase difference between the P-polarized light and the S-polarized light before and after reflection and before and after transmission is δ, a phase-free polarization beam splitter A as defined below,
A ', B, B', a phase-free polarizing beam splitter C, and a polarizing beam splitter PBS are used.

A: Tp = 100%, Rp = 0%, Ts =
A ': Tp = Rp = 50%, Ts = 100%, Rs = 0
%, Δ = 0 ° B: Tp = 0%, Rp = 100%, Ts = Rs = 50
%, Δ = 0 ° B ′: Tp = Rp = 50%, Ts = 0%, Rs = 100
%, Δ = 0 ° C: Tp = Rp = Ts = Rs = 50%, δ = 0 ° PBS: Tp = Rs = 100%, Rp = Ts = 0% The first wavefront splitting system of the present invention is shown in FIG. As shown in A,
It is configured by combining two of the non-phase polarizing beam splitters A ', B and B' with the polarizer P. In the drawing, the vibration directions of the P-polarized light and the S-polarized light are represented by either the x-axis direction or the y-axis direction. The incident light is split into two light fluxes of transmitted light and reflected light by the non-phase polarized beam splitter, and when isotropic light is incident, the side on which both P-polarized light and S-polarized light are output is a-side, The side that outputs only one side is b
Side.

A second prism is installed on the a side of the first prism, and the b-side output light of the first prism and the b-side output light of the second prism become linearly polarized light orthogonal to each other, and It is arranged so that the side output light becomes isotropic light.
Further, the polarizer P is disposed on the a side of the second prism so that the transmission axis is oriented in a direction rotated by 45 ° from the P-polarized light and the S-polarized light.

The b-side output light intensity I ₁ of the first prism and the b-side output light intensity I of the second prism when the light from the light source is directly incident on the polarization splitting element without passing through the optical rotatory substance S. The transmitted light intensity I ₃ of the _two polarizers and the respective output light intensity I ₁ ′ when the light transmitted through the optical rotatory substance S is made incident,
Measure I ₂ ′ and I ₃ ′.

FIG. 2A shows a state in which the optical rotatory substance S is not inserted, and FIG. 2B shows a state in which the optical rotatory substance S is inserted.

As shown in FIG. 3, the second wavefront splitting system according to the present invention is configured by combining a phaseless non-polarizing beam splitter C, a polarizing beam splitter PBS, and a polarizer P. The PBS is installed on either the transmission side or the reflection side of the beam splitter C, and the polarizer P is installed on the other side. The P-polarized light and S-polarized light of PBS are set to be either P-polarized light or S-polarized light of C, and the polarizer P is set so that the transmission axis faces the azimuth rotated by 45 ° from the P-polarized light of C or S-polarized light. You.

The two output light intensities I ₁ and I ₂ of the PBS and the transmitted light intensity I ₃ of the PBS 2 when the light from the light source is directly incident on the polarization splitting element without passing through the optical rotatory substance S.
And the output light intensities I ₁ ′, I ₂ ′, and I ₃ ′ when the light transmitted through the optical rotatory substance S is incident.

[0017]

The output light intensities I ₁ , I ₂ , and I ₃ are as follows when the incident light is linearly polarized light of intensity 1 inclined by an angle θ from the x-axis direction as shown in FIGS.

[0018] ^{_{I 1 = 1/2 cos 2}} θ (1) I 2 = 1/2 sin 2 θ (2) I 3 = 1/2 sin 2 (θ + 45 °) (3) From this theta is theta = cos ^{- ₁} √2I ¹ (4) obtained as _{^{θ = sin -1 √2I 2 (5}} ) θ = sin -1 √2I 3 -45 ° (6).

On the other hand, the output light intensity when the light transmitted through the optical rotation material S having the optical rotation angle α is incident is similarly I ₁ ′ = １ ／ cos ² (θ + α) (7) I ₂ ′ = 1 / 2 sin ² (θ + α) (8) I ₃ ′ = 1/2 sin ² (θ + α + 45 °) (9) α = cos ⁻¹ √2I ₁ ′ −θ (10) α = sin ⁻¹ √2I ₂ ′ − θ (11) α = sin ⁻¹ √2I ₃ ′ −θ−45 ° (12)

Θ is obtained from (4) to (6), and the optical rotation angle α is (10)
~ (12). It is also possible to determine θ from the one showing the strongest intensity among I ₁ , I ₂ , and I ₃ , or to average θ obtained from two intensities, or to average θ obtained from three intensities. It does not matter.

0 °, 90 °, 45 ° from x axis
Since the intensity of the linearly polarized light oscillating in the direction of is measured, it is unlikely that the intensity becomes weak enough to make it difficult to measure at least three. If the light having sufficient intensity is selected and measured, an accurate value of θ can be obtained. Similarly to θ, the optical rotation angle α can be accurately obtained.

[0022]

FIG. 4 shows a first embodiment of the wavefront splitting element according to the present invention. In the first embodiment, two non-phase polarized beam splitters A and a polarizer P are used. The transmitted P polarized light and the transmitted S polarized light of the first beam splitter A become incident S polarized light and incident P polarized light of the second beam splitter A, respectively. The polarizer P is disposed on the transmission side of the second beam splitter such that the transmission axis is rotated by 45 ° from the P-polarized light or the S-polarized light. The reflective side of the first beam splitter 50% of S-polarized light component E ₉₀ of the incident light is outputted, the reflective side of the second beam splitter is output 50% of the P polarized light component E _0, incident from the polarizer Light polarization angle 45 ° component E ₄₅ 50
% Is output.

FIG. 5 shows a second modification of the first embodiment. In the second embodiment, a half-wave plate HWP is inserted between the first beam splitter and the second beam splitter of the first embodiment,
By inverting the oscillation directions of the P-polarized light and the S-polarized light emitted from the first beam splitter, the incident light, the first
The four lights of the reflected light of the beam splitter, the reflected light of the second beam splitter, and the transmitted light of the polarizer are made to travel in the same plane.

FIG. 6 shows a third embodiment. Embodiment 3 is composed of two phase-free polarization beam splitters A 'and a polarizer P, and transmits P polarized light and transmitted S light of the first beam splitter A'.
The polarized light was arranged so as to be incident S-polarized light and incident P-polarized light of the second beam splitter A ′, respectively, and the transmission axis was rotated by 45 ° from the P-polarized light and the S-polarized light toward the transmission side of the second beam splitter. Arrange so that it becomes the direction. First
50% of E ₀ is output to the reflection side of the beam splitter, and 50% of E ₉₀ is output to the reflection side of the second beam splitter.
Is output, and 50% of E ₄₅ is output from the polarizer.

FIG. 7 shows a fourth embodiment which is a modification of the third embodiment. In the fourth embodiment, a half-wave plate HWP is inserted between the first beam splitter and the second beam splitter of the third embodiment,
By inverting the oscillation directions of the P-polarized light and the S-polarized light emitted from the first beam splitter, the incident light, the first
The four lights of the reflected light of the beam splitter, the reflected light of the second beam splitter, and the transmitted light of the polarizer are made to travel in the same plane.

FIG. 8 shows a fifth embodiment. The fifth embodiment includes two non-phase polarizing beam splitters B and a polarizer P, and the reflected P polarized light and the reflected S polarized light of the first beam splitter B are incident S polarized light of the second beam splitter B, respectively.
The polarizer P is disposed so as to be incident P-polarized light, and the polarizer P is disposed on the reflection side of the second beam splitter such that the transmission axis is rotated by 45 ° from the P-polarized light or the S-polarized light. The permeate side of the first beam splitter is output 50% of E _90,
50% of E ₀ is output to the transmission side of the second beam splitter, and 50% of E ₄₅ is output from the polarizer.

FIG. 9 shows a sixth modification of the fifth embodiment. In the sixth embodiment, a half-wave plate HWP is inserted between the first beam splitter and the second beam splitter of the fifth embodiment,
By inverting the oscillation directions of the P-polarized light and the S-polarized light emitted from the first beam splitter, the incident light, the first
Four lights, that is, light transmitted by the beam splitter, light transmitted by the second beam splitter, and light transmitted by the polarizer are made to travel in the same plane.

FIG. 10 shows a seventh embodiment. In the seventh embodiment, two non-phase polarizing beam splitters B 'and a polarizer P are used, and the reflected P-polarized light and the reflected S-polarized light of the first beam splitter B' are respectively incident on the second beam splitter B '.
Polarized light and incident P-polarized light, and the polarizer P is positioned such that the transmission axis is P-polarized light or S-polarized light on the reflection side of the second beam splitter.
They are arranged so as to be rotated by 45 ° from the polarized light. 50% of E ₀ is output to the transmission side of the first beam splitter, and 50% of E ₉₀ is output to the transmission side of the second beam splitter.
%, And 50% of E ₄₅ is output from the polarizer.

FIG. 11 shows a modified embodiment 8 of the seventh embodiment.
In the eighth embodiment, the first beam splitter of the seventh embodiment and the second beam splitter
By inserting a half-wave plate HWP between the beam splitters and inverting the oscillation directions of the P-polarized light and the S-polarized light emitted from the first beam splitter, the incident light,
Four lights, that is, light transmitted by the first beam splitter, light transmitted by the second beam splitter, and light transmitted by the polarizer are made to travel in the same plane. FIG. 12 shows a ninth embodiment. The ninth embodiment is directed to the non-phase polarizing beam splitters A and B and the polarizer P.
And the transmission P-polarized light and the transmission S-polarized light of the first beam splitter A are arranged so as to be incident S-polarized light and incident P-polarized light of the second beam splitter B, respectively, and the polarizer P is reflected by the second beam splitter. It is arranged so that the transmission axis has an orientation rotated by 45 ° from the P-polarized light or the S-polarized light. The reflective side of the first beam splitter 50% E ₉₀
Is output, and E ₀ is provided on the transmission side of the second beam splitter.
Is output, and 50% of E ₄₅ is output from the polarizer.

FIG. 13 shows a tenth modification of the ninth embodiment. In the tenth embodiment, a half-wave plate HWP is inserted between the first beam splitter and the second beam splitter of the ninth embodiment to reverse the oscillation directions of the P-polarized light and the S-polarized light emitted from the first beam splitter. Thereby, the four lights of the incident light, the reflected light of the first beam splitter, the transmitted light of the second beam splitter, and the transmitted light of the polarizer are made to travel in the same plane.

FIG. 14 shows an eleventh embodiment. In the eleventh embodiment, the non-phase polarizing beam splitters B and A and the polarizer P are used, and the reflected P polarized light and the reflected S polarized light of the first beam splitter B become the incident S polarized light and the incident P polarized light of the second beam splitter A, respectively. And the polarizer P is arranged on the transmission side of the second beam splitter such that the transmission axis is rotated by 45 ° from the P-polarized light or the S-polarized light. First
50% of E ₉₀ is output on the transmission side of the beam splitter, and 50% of E ₀ is output on the reflection side of the second beam splitter.
Is output, and 50% of E ₄₅ is output from the polarizer.

FIG. 15 shows a twelfth modification of the eleventh embodiment. In the twelfth embodiment, a half-wave plate HWP is provided between the first beam splitter and the second beam splitter of the eleventh embodiment.
Is inserted, and P coming out of the first beam splitter
By inverting the oscillation directions of the polarized light and the S-polarized light, four lights of incident light, transmitted light of the first beam splitter, reflected light of the second beam splitter, and transmitted light of the polarizer travel in the same plane. To

FIG. 16 shows a thirteenth embodiment. The thirteenth embodiment includes phase-free polarization beam splitters A ′ and B ′ and a polarizer P, and the transmission P-polarized light and the transmission S-polarized light of the first beam splitter A ′ are respectively the second beam splitter B ′.
And the polarizer P is arranged such that the transmission axis is P on the reflection side of the second beam splitter.
It is arranged so as to be in an azimuth rotated by 45 ° from polarized light or S-polarized light. The reflective side of the first beam splitter 50 E ₀
%, And E on the transmission side of the second beam splitter.
Output 50% of _90, from the polarizer output 50% of E _45.

FIG. 17 shows a fourteenth embodiment which is a modification of the thirteenth embodiment. In the fourteenth embodiment, a half-wave plate HWP is provided between the first beam splitter and the second beam splitter of the thirteenth embodiment.
Is inserted, and P coming out of the first beam splitter
By inverting the oscillation directions of the polarized light and the S-polarized light, the four lights of incident light, reflected light of the first beam splitter, transmitted light of the second beam splitter, and transmitted light of the polarizer travel in the same plane. To

FIG. 18 shows a fifteenth embodiment. In the fifteenth embodiment, the non-phase polarizing beam splitters B ′ and A ′ and the polarizer P are used, and the reflected P polarized light and the reflected S polarized light of the first beam splitter B ′ are respectively the second beam splitter A ′.
And the polarizer P is positioned such that the transmission axis is on the transmission side of the second beam splitter.
It is arranged so as to be in an azimuth rotated by 45 ° from polarized light or S-polarized light. E ₀ of 50 is on the transmission side of the first beam splitter.
%, And E on the reflection side of the second beam splitter.
Output 50% of _90, from the polarizer output 50% of E _45.

FIG. 19 shows a sixteenth modification of the fifteenth embodiment. In the sixteenth embodiment, a half-wave plate HWP is provided between the first beam splitter and the second beam splitter of the fifteenth embodiment.
Is inserted, and P coming out of the first beam splitter
By inverting the oscillation directions of the polarized light and the S-polarized light, four lights of incident light, transmitted light of the first beam splitter, reflected light of the second beam splitter, and transmitted light of the polarizer travel in the same plane. To

FIG. 20 shows a seventeenth embodiment. Example 17 is composed of phase-free polarization beam splitters A and A ′ and a polarizer P, and the transmission P polarization and transmission S polarization of the first beam splitter A are respectively incident P polarization and incident S polarization of the second beam splitter A ′. And the polarizer P
Are arranged on the transmission side of the second beam splitter so that the transmission axis is rotated by 45 ° from P-polarized light or S-polarized light.
50% of E ₉₀ is output to the reflection side of the first beam splitter, and 5% of E ₀ is output to the reflection side of the second beam splitter.
0% is output, and 50% of E ₄₅ is output from the polarizer.

FIG. 21 shows an eighteenth embodiment. Example 18 is composed of phase-free polarization beam splitters A ′, A and a polarizer P, and transmits P-polarized light of the first beam splitter A ′,
The transmission S-polarized light is arranged so as to be incident P-polarized light and incident S-polarized light of the second beam splitter A, respectively, and the polarizer P
Are arranged on the transmission side of the second beam splitter so that the transmission axis is rotated by 45 ° from P-polarized light or S-polarized light.
50% of E ₀ is output to the reflection side of the first beam splitter, and 5% of E ₉₀ is output to the reflection side of the second beam splitter.
0% is output, and 50% of E ₄₅ is output from the polarizer.

FIG. 22 shows a nineteenth embodiment. Embodiment 19 In Embodiment 19, the P-polarized light and the S-polarized light of the first beam splitter B are respectively composed of the P-polarized light and the S-polarized light of the second beam splitter B '. And the polarizer P
Are arranged on the reflection side of the second beam splitter such that the transmission axis is rotated by 45 ° from the P-polarized light or the S-polarized light.
50% of E ₉₀ is output to the transmission side of the first beam splitter, and 5% of E ₀ is output to the transmission side of the second beam splitter.
0% is output, and 50% of E ₄₅ is output from the polarizer.

FIG. 23 shows a twentieth embodiment. The twentieth embodiment includes the non-phase polarization beam splitters B ′ and B and the polarizer P, and the reflection P polarization of the first beam splitter B ′,
Arranged so that the reflected S-polarized light becomes the incident P-polarized light and the incident S-polarized light of the second beam splitter B, respectively, and the polarizer P
Are arranged on the reflection side of the second beam splitter such that the transmission axis is rotated by 45 ° from the P-polarized light or the S-polarized light.
50% of E ₀ is output on the transmission side of the first beam splitter, and 5% of E ₉₀ is output on the transmission side of the second beam splitter.
0% is output, and 50% of E ₄₅ is output from the polarizer.

FIG. 24 shows a twenty-first embodiment. Example 21 is composed of the non-phase polarized beam splitters A and B 'and the polarizer P, and the transmitted P polarized light and transmitted S polarized light of the first beam splitter A are incident P polarized light and incident S polarized light of the second beam splitter B', respectively. And the polarizer P
Are arranged on the reflection side of the second beam splitter such that the transmission axis is rotated by 45 ° from the P-polarized light or the S-polarized light.
50% of E ₉₀ is output to the reflection side of the first beam splitter, and 5% of E ₀ is output to the transmission side of the second beam splitter.
0% is output, and 50% of E ₄₅ is output from the polarizer.

FIG. 25 shows a twenty-second embodiment. Embodiment 22 is composed of the non-phase polarization beam splitters B ′ and A and the polarizer P, and the reflection P polarization of the first beam splitter B ′,
Arranged so that the reflected S-polarized light becomes the incident P-polarized light and the incident S-polarized light of the second beam splitter A, respectively.
Are arranged on the transmission side of the second beam splitter so that the transmission axis is rotated by 45 ° from P-polarized light or S-polarized light.
50% of E ₀ is output to the transmission side of the first beam splitter, and 5% of E ₉₀ is output to the reflection side of the second beam splitter.
0% is output, and 50% of E ₄₅ is output from the polarizer.

FIG. 26 shows a twenty-third embodiment. Example 23 is composed of phase-free polarization beam splitters A ′ and B and a polarizer P, and transmits P-polarized light of the first beam splitter A ′.
The transmission S-polarized light is arranged so as to be incident P-polarized light and incident S-polarized light of the second beam splitter B, respectively, and the polarizer P
Are arranged on the reflection side of the second beam splitter such that the transmission axis is rotated by 45 ° from the P-polarized light or the S-polarized light.
50% of E ₀ is output to the reflection side of the first beam splitter, and 5% of E ₉₀ is output to the transmission side of the second beam splitter.
0% is output, and 50% of E ₄₅ is output from the polarizer.

FIG. 27 shows a twenty-fourth embodiment. In the twenty-fourth embodiment, the reflection P-polarized light and the reflected S-polarized light of the first beam splitter B are incident P-polarized light and incident S-polarized light of the second beam splitter A ', respectively. And the polarizer P
Are arranged on the transmission side of the second beam splitter so that the transmission axis is rotated by 45 ° from P-polarized light or S-polarized light.
50% of E ₉₀ is output on the transmission side of the first beam splitter, and 5% of E ₀ is output on the reflection side of the second beam splitter.
0% is output, and 50% of E ₄₅ is output from the polarizer.

FIGS. 28 to 31 show Embodiments 25 to 28.
Embodiments 25 to 28 all include a non-phase and non-polarization beam splitter C, a polarization beam splitter PBS and a polarizer P.

In the twenty-fifth embodiment, the transmission P-polarized light and the transmission S-polarized light of C are arranged so as to be the incident P-polarized light and the incident S-polarized light of the PBS, respectively. They are arranged so as to be rotated by 45 ° from the S-polarized light. 50% of E ₀ is output on the transmission side of the PBS, 50% of E ₉₀ is output on the reflection side, and 5% of E ₄₅ is output from the polarizer.
0% is output.

In Embodiment 26, the reflected P-polarized light and the reflected S-polarized light of C are arranged so as to become the incident P-polarized light and the incident S-polarized light of the PBS, respectively. They are arranged so as to be rotated by 45 ° from the S-polarized light. 50% of E ₀ is output on the transmission side of the PBS, 50% of E ₉₀ is output on the reflection side, and 5% of E ₄₅ is output from the polarizer.
0% is output.

In the embodiment 27, the transmitted P-polarized light and the transmitted S-polarized light of C are arranged so as to become the incident S-polarized light and the incident P-polarized light of the PBS, respectively. They are arranged so as to be rotated by 45 ° from the S-polarized light. 50% of E ₉₀ is output on the transmission side of the PBS, 50% of E ₀ is output on the reflection side, and 5% of E ₄₅ is output from the polarizer.
0% is output.

In the embodiment 28, the reflected P-polarized light and the reflected S-polarized light of C are arranged so as to become the incident S-polarized light and the incident P-polarized light of the PBS, respectively, and the polarizer P is disposed on the transmission side of the C with the transmission axis of the P-polarized light. They are arranged so as to be rotated by 45 ° from the S-polarized light. 50% of E ₉₀ is output on the transmission side of the PBS, 50% of E ₀ is output on the reflection side, and 5% of E ₄₅ is output from the polarizer.
0% is output.

[0050]

When the angle of rotation is measured using the wavefront splitting element of the present invention, the mechanical life of the apparatus is considerably increased as compared with the conventional method because there is no movable part.

Since it is not necessary to detect the extinction position by using the method of the present invention, it is not necessary for the photoelectric detector to follow a sudden change in the intensity of the detection light. Since light having a sufficient intensity can be selected as a bonus, there is no need to detect weak light, and the measurement accuracy of the optical rotation angle is dramatically improved as compared with the conventional method.

[Brief description of the drawings]

FIG. 1 is a diagram showing the measurement principle of a conventional polarimeter, and FIG.
Represents a state in which no optical rotation substance is inserted, and (b) represents a state in which an optical rotation substance is inserted.

FIG. 2 shows the principle of an optical system that uses two phase-free polarization beam splitters and a polarizer among the wavefront splitting elements of the present invention. FIG. 2 (a) shows a state in which no optical rotation substance is inserted, and FIG. ) Indicates a state in which the optical rotation substance is inserted.

FIG. 3 shows the principle of an optical system that uses a phaseless non-polarizing beam splitter, a polarizing beam splitter, and a polarizer among the wavefront splitting elements of the present invention. (B) shows the state where the optical rotation substance is inserted.

FIG. 4 shows a first embodiment of a wavefront splitting element according to the present invention,
Two and P are used.

FIG. 5 illustrates a second modification of the first embodiment of the wavefront splitting device according to the present invention, in which HWP is used in addition to A2 and P;

FIG. 6 shows a wavefront splitting element according to a third embodiment of the present invention;
Two A's and P are used.

FIG. 7 shows a fourth modification of the third embodiment of the wavefront splitting element of the present invention, in which HWP is used in addition to two A's and P's.

FIG. 8 shows a fifth embodiment of the wavefront splitting element of the present invention,
Two and P are used.

FIG. 9 shows a modification 6 of the fifth embodiment of the wavefront splitting element of the present invention, wherein HWP is used in addition to B2 and P;

FIG. 10 shows a seventh embodiment of the wavefront splitting element of the present invention;
Two B's and P are used.

FIG. 11 shows a modification 8 of the seventh embodiment of the wavefront dividing element of the present invention, in which HWP is used in addition to two B's and P's.

FIG. 12 shows a wavefront splitting element according to a ninth embodiment of the present invention;
A, B, and P are used.

FIG. 13 shows a tenth modification of the ninth embodiment of the wavefront splitting element of the present invention, in which HWP is used in addition to A, B, and P.

FIG. 14 shows an eleventh embodiment of the wavefront splitting element of the present invention, in which B, A, and P are used.

15 shows a twelfth modified example of the eleventh embodiment of the wavefront splitting element of the present invention, in which HWP is used in addition to B, A and P. FIG.

FIG. 16 shows a wavefront splitting element according to a thirteenth embodiment of the present invention, in which A ′, B ′, and P are used.

FIG. 17 shows a modification 14 of the thirteenth embodiment of the wavefront splitting element of the present invention, in which HWP is used in addition to A ′, B ′ and P.

FIG. 18 illustrates a wavefront splitting element according to a fifteenth embodiment of the present invention, in which B ′, A ′, and P are used.

FIG. 19 shows a modification 16 of the fifteenth embodiment of the wavefront dividing element of the present invention, in which HWP is used in addition to B ′, A ′, and P.

FIG. 20 illustrates a seventeenth embodiment of the wavefront splitting element according to the present invention, in which A, A ′, and P are used.

FIG. 21 shows an eighteenth embodiment of the wavefront splitting element of the present invention, in which A ′, A, and P are used.

FIG. 22 shows a wavefront splitting element according to a nineteenth embodiment of the present invention, in which B, B ′, and P are used.

FIG. 23 shows a wavefront splitting element according to a twentieth embodiment of the present invention, in which B ′, B, and P are used.

FIG. 24 shows an embodiment 21 of the wavefront splitting element of the present invention, in which A, B ′, and P are used.

FIG. 25 shows a wavefront splitting element according to a twenty-second embodiment of the present invention, in which B ′, A, and P are used.

FIG. 26 shows a wavefront splitting element according to a twenty-third embodiment of the present invention, in which A ′, B, and P are used.

FIG. 27 shows a twenty-fourth embodiment of the wavefront splitting element according to the present invention, in which B, A ′, and P are used.

FIG. 28 illustrates a wavefront splitting element according to a twenty-fifth embodiment of the present invention, in which C, PBS, and P are used.

FIG. 29 illustrates a wavefront splitting element according to a twenty-sixth embodiment of the present invention, in which C, PBS, and P are used.

FIG. 30 shows a twenty-seventh embodiment of the wavefront splitting element of the present invention, in which C, PBS, and P are used.

FIG. 31 shows an embodiment 28 of the wavefront splitting element of the present invention, in which C, PBS, and P are used.

[Explanation of symbols]

 P Polarizer N Analyzer S Optical rotation substance A, A ', B, B' Phase-free polarization beam splitter C Phase-free non-polarization beam splitter PBS Polarization beam splitter

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G01N 21/00-21/01 G01N 21/17-21/61 G01J 4/00-4/04 G01B 9/00-9 / 10 G01B 11/00-11/30 JICST file (JOIS) Practical file (PATOLIS) Patent file (PATOLIS)

Claims (3)

(57) [Claims] 1. A first beam splitter comprising two elements, a phaseless polarization beam splitter and a polarizer, wherein transmitted or reflected P-polarized light and transmitted or reflected S-polarized light of a first beam splitter are respectively incident S-polarized light of a second beam splitter. , And the polarizer is arranged on the transmission or reflection side of the second beam splitter such that the transmission axis is rotated by 45 ° from P-polarized light or S-polarized light. Wavefront splitting element. 2. The wavefront splitting device according to claim 1, wherein a half-wave plate is inserted between the first beam splitter and the second beam splitter.
The oscillation directions of the P-polarized light and the S-polarized light emitted from the beam splitter are inverted, and the incident light, the reflected light of the first beam splitter, the reflected light of the second beam splitter, and the emitted light of the polarizer are changed. A wavefront splitting element, wherein light is arranged to travel in the same plane. 3. A non-phase non-polarization beam splitter, a polarization beam splitter, and a polarizer, each of which has a transmission or reflection P polarization and a transmission or reflection S polarization of a phase non-polarization first beam splitter. The second polarizing beam splitter is arranged so as to be incident P-polarized light and incident S-polarized light, and the polarizer is disposed at the transmission or reflection side of the first beam splitter so that the transmission axis is at 45 ° from the P-polarized light or the S-polarized light.
A wavefront splitting element, wherein the wavefront splitting element is arranged to have a rotated azimuth.