Multi-band spectrum division device

Abstract

A multi-band spectrum division device is provided, comprising: a first parabolic reflection mirror, planar multi-mirrors, an optical grating and a second parabolic mirror. The first parabolic mirror is configured to reduce the divergent angle of incident optical beam, and to generate a collimated optical beam. The planar multi-mirrors are configured to adjust the incident angles of collimated beam on the grating surface. The grating is configured to disperse the incident signals with multi-wavelengths. The second parabolic mirror is configured to focus the multi-wavelength signals on its focal plane. Besides, each of the planar multi-mirrors has different location and angle in this device.

Claims

1. A multi-band spectrum division device, comprising: a first parabolic reflection mirror, configured to reduce the divergent angle of incident optical beam and to generate a collimated optical beam; a first planar reflection mirror located at a first location with a first angular orientation with respect to an optical path, a second planar reflection mirror located at a second location with a second angular orientation with respect to the optical path, wherein the second reflection mirror may be moved or rotated into or out of the optical beam path, the planar reflection mirrors each is configure to reflect multi-band of the collimated optical beam; a diffraction grating, configured to receive the reflected multi-band collimated optical beam from the first reflection mirror with a first incident angle when the second planar mirror is moved or rotated out of the optical beam path or to receive the reflected multi-band collimated optical beam from the second reflection mirror with a second incident angle when the second planar mirror is moved or rotated into the optical beam path, the grating is to diffract and disperse the received multi-band collimated optical beam; and a second parabolic reflection mirror, configured to focus the band of optical beam diffracted from the diffraction grating on a focal plane.

2. The multi-band spectrum division device as claimed in claim 1, wherein the diffraction grating has a plurality of straight notches, wherein a distance between each adjacent straight notch is D.

3. The multi-band spectrum division device as claimed in claim 2, wherein the distance D is between 0.6 m and 5.0 m.

4. The multi-band spectrum division device as claimed in claim 1, wherein the diffraction grating receives the collimated optical beam at a specific angle of incident n, wherein the n is a nature number indicated n-th wavelength band .sub.n, and the diffraction grating divides and diffracts the n-th wavelength band of the collimated optical beam into a specific angle direction d, according to the diffraction equation D(sin dsin n)=mn, m being an integer.

5. The multi-band spectrum division device as claimed in claim 4, wherein the first and second planar reflection mirrors can move into the optical beam path of the multi-band spectrum division device to reflect the multi-band of the collimated optical beam to the diffraction grating of the multi-band spectrum division device, so that meets the diffraction equation.

6. The multi-band spectrum division device as claimed in claim 4, wherein the first and second planar reflection mirrors can rotate into the optical beam path of the multi-band spectrum division device to reflect the multi-band of the collimated optical beam to the diffraction grating of the multi-band spectrum division device, so that meets the diffraction equation.

7. The multi-band spectrum division device as claimed in claim 6, wherein the planar reflection mirrors can rotate with an endpoint of itself.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1A is a schematic diagram in one embodiment of this invention.

(2) FIG. 1B is a schematic diagram in another embodiment of this invention.

(3) FIG. 1C is a schematic diagram in another embodiment of this invention.

(4) FIG. 2 is a schematic diagram in another embodiment of this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(5) Please refer to FIG. 1A. A multi-band spectrum division device 11 in this embodiment comprising a first parabolic reflection mirror 12, a second planar reflection mirrors 13 for a second wave band, a first planar reflection mirrors 14 for a first wave band, a grating 15, a second parabolic reflection mirror 16, a slit 17, and a processing device 18. An incident optical signal V from a test sample includes two wave bands optical signals. The optical signal V emits into the multi-band spectrum division device 11 through the slit 17. The slit 17 can filter stray light of the optical signal V, so that only the divergent optical beam in narrow range can emit.

(6) The filtered optical signal V emits into the first parabolic reflection mirror 12. The first parabolic reflection mirror 12 collimates the optical signal V into a collimated optical beam C and guides it to the second planar reflection mirrors 13 for a second wave band. In this embodiment, the first parabolic reflection mirror 12 is configured to reduce the divergent angle of collimated optical beam C, wherein the divergent angle is between 1010.

(7) The second planar reflection mirrors 13 for the second wave band reflects the collimated optical beam C to the grating 15. The grating 15 is configured to receive the collimated optical beam C reflected from the second planar reflection mirrors 13 for the second wave band. The grating 15 disperses a second wave band of the collimated optical beam C according to different wavelength. In this embodiment, the grating 15 is a linear grating, but not limited thereto. The grating 15 has a plurality of straight notches (not shown), wherein a distance between each adjacent notches is D. The second wave band of the collimated optical beam C with center wavelength 2, emits with 2 angle to the grating 15, and emergent from the grating 15 with d angle. In this circumstance, this system meets the mathematical equation:
D(sin dsin 2)=2.

(8) The second parabolic reflection mirror 16 focuses the second wave band optical signal with different wavelength reflected from the grating 15 on a position near a focal plane of the second parabolic reflection mirror 16 or the receiving area of the processing device 18. The processing device 18 may be a detector, like a light detector, but not limited thereto. The processing device 18 can determine the proportion percentage of each wavelength of the incident optical beam according to the incident position of the optical beam. In another embodiment, the processing device 18 also can connect with external device (e.g. computer or other similar device) to proceed follow-up analysis or storing.

(9) Still refer to FIG. 1A, the multi-band spectrum division device 11 further comprising a first planar reflection mirror 14 for the first wave band, configured to reflect the collimated optical beam C to the grating 15, like the second planar reflection mirrors 13 for the second wave band. It is noted that, in this embodiment, the locations and angles of the first planar reflection mirror 14 and the second planar reflection mirrors 13 are different. As shown in FIG. 1A, the first planar reflection mirror 14 is disposed between the second planar reflection mirrors 13 and the first parabolic reflection mirror 12. It is noted that the first planar reflection mirror 14 can move or rotate to enter or leave an optical beam path of the multi-band spectrum division device 11. In this embodiment, the first planar reflection mirror 14 can move back and forth on the path which is perpendicular to the collimated optical beam C from the first parabolic reflection mirror 12 to the second planar reflection mirrors 13. The first planar reflection mirror 14 for the first wave band can be connected with a moving device such as motor or the like.

(10) When the first planar reflection mirror 14 enters the path of the collimated optical beam C, the collimated optical beam C is reflected to the grating 15 by the first planar reflection mirror 14. At this time, an optical beam with a first center wavelength 1 of the collimated optical beam C emits to the grating 15 with 1 incident angle. In addition, by adjusting the location of the first planar reflection mirror 14, and the relative angle between the first planar reflection mirror 14 and the grating 15, the center wavelength 1 of the first wave band of the collimated optical beam C will emerge from the grating 15 with the same angle d. In this circumstance, this system meets the mathematical equation: D(sin dsin 1)=1. Similarly, the second parabolic reflection mirror 16 focuses the second wave band optical signal with different wavelength reflected from the grating 15 on a position near a focal plane of the second parabolic reflection mirror 16 or the receiving area of the processing device 18.

(11) As set forth above two circumstances, by adjusting the locations of the first planar reflection mirror 14 or the second planar reflection mirrors 13, and the relative angles between the first planar reflection mirror 14 or the second planar reflection mirrors 13 and the grating 15, it makes the center wavelength n of the each wave band of the collimated optical beam C emit with different incident angle respectively, and emerge with the same emergent angle of each wave band.

(12) Accordingly, the multi-band spectrum division device 11, in this embodiment, take two-band spectrum division device for example, n is 1 and 2. If it is three-band spectrum division device, n is 1, 2 and 3. That is, the multi-band spectrum division device, n is 1, 2, 3, . . . . The n is a nature number.

(13) In another embodiment of this invention, as shown in FIG. 1B. The first planar reflection mirror 14 for the first wave band takes an endpoint as a shaft, and rotates with the endpoint to enter the optical beam path of the two-band spectrum division device 11. It is noted that, in this embodiment, the first planar reflection mirror 14 rotates 90 to enter the path, but not limited thereto. The first planar reflection mirror 14 can connect with a rotating device or revolving device to rotate.

(14) In another embodiment of this invention, as shown in FIG. 1C. The first planar reflection mirror 14 can move up and down to enter or leave the optical beam path of the two-band spectrum division device 11.

(15) In another embodiment of this invention, using single planar reflection mirror to finish switching two wave band detecting signals, as shown in FIG. 2. The planar reflection mirror 14 and an incident optical beam have an angle 14. It makes an optical beam with a first center wavelength 1 of the collimated optical beam C emit to the grating 15 with angle 1 and meet an mathematical equation D(sin dsin 1)=1 to detect the spectrum signal of the first wave band. When detecting the spectrum signal of the second wave band, the planar reflection mirror can move to the location 13, and has an angle 13 with the incident optical beam. It makes an optical beam with a first center wavelength 2 of the collimated optical beam C emit to the grating 15 with angle 2 and meet an mathematical equation D(sin dsin 2)=2.

(16) Compared to the prior art, the multi-band spectrum division device in this invention has a relative simple structure. It can reduce the cost and has much wider ranges of detecting wave band in the same resolution.

(17) Although the preferred embodiments of the present invention have been described herein, the above description is merely illustrative. Further modification of the invention herein disclosed will occur to those skilled in the respective arts and all such modifications are deemed to be within the scope of the invention as defined by the appended claims.