Wide continuous spectrum solid spectrum laser

Abstract

The invention relates to a wide continuous spectrum laser, which comprises a resonant cavity, pumping laser and a laser gain medium, and is characterized in that a dispersion element is arranged between the laser gain medium and a laser output cavity mirror, and the dispersion element is positioned on a laser light path; the laser gain medium has a wide gain bandwidth. According to the invention, the optical path of the light with different wavelengths emitted by the laser gain medium is changed through the dispersion device, so that the light with different wavelengths can generate oscillation starting at different positions of the laser gain medium, and the resonant cavity can generate wide continuous spectrum laser. Compared with a broadband spectrum laser adopting a nonlinear effect, the conversion efficiency is higher, very high laser peak power is not needed, and the cost is low. Moreover, a common light source can be used as the light source, so that the peak power of the laser is better controlled, and the application range of the laser is wider.

Description

Technical Field

[0001] The invention relates to a wide continuous spectrum laser, belonging to the technical field of wide spectrum lasers. Background Art

[0002] Broad-spectrum lasers are special lasers that have both the high brightness and high coherence of traditional lasers and a much wider spectral range than general lasers. After years of development, broad-spectrum lasers have shown important application value in biomedical imaging, hyperspectral laser radar, blood testing, military optoelectronic confrontation and other application fields.

[0003] At present, the main method of generating a wide spectrum is to use the nonlinear effect of high-power density lasers in nonlinear optical media. Under the combined effect of the nonlinear effect and the dispersion of the incident laser by the medium, the spectrum of the incident laser will be strongly broadened in the nonlinear medium, continuously generating new frequency components, and finally forming a wide-spectrum laser output, which is also called a supercontinuum.

[0004] In the prior art, the method of generating a wide spectrum, i.e., a supercontinuum spectrum, is to use nonlinear effects, such as the Chinese patents with application numbers CN202010187860.6 and CN202222368644.9. The conversion efficiency of nonlinear effects is very low. To produce significant nonlinear effects, a very high laser peak power is required, and ultrafast lasers are conventionally used as light sources. Such wide-spectrum lasers are very expensive. Moreover, since the light source is a pulsed laser, the generated wide-spectrum light source is also a pulsed laser, and its peak power is also relatively strong, which is not suitable for some application scenarios, such as biomedical testing equipment, and high peak power will damage biological samples. Summary of the invention

[0005] In order to overcome the above problems, the present invention provides a wide continuous spectrum laser, which generates lasers of different wavelengths at different positions of a laser gain medium through a dispersion element, and then combines the beams using the dispersion element to generate wide continuous spectrum lasers.

[0006] The technical solution of the present invention is as follows:

[0007] A wide continuous spectrum laser comprises a resonant cavity, a pump laser and a laser gain medium, and further comprises: a dispersion element is arranged between the laser gain medium and a laser output cavity mirror, the dispersion element is located on the laser optical path; the laser gain medium has a wide gain bandwidth.

[0008] Furthermore, the dispersion element is a diffraction grating, a prism, a combination of a diffraction grating and a diffraction grating, a combination of a prism and a prism, or a combination of a diffraction grating and a prism.

[0009] Furthermore, the diffraction grating is a reflection grating or a transmission grating.

[0010] Furthermore, the diffraction grating is a planar grating, a non-planar grating or a volume grating.

[0011] Furthermore, the dispersion element includes a first reflection grating and a second reflection grating, the first reflection grating and the second reflection grating are parallel, and the light emitted by the laser gain medium is reflected by the first reflection grating, reaches the second reflection grating, and then reflects by the second reflection grating to reach the laser output cavity mirror.

[0012] Furthermore, the laser output cavity mirror is a laser output coupling cavity mirror.

[0013] Furthermore, the pump laser is side-pumped or end-pumped on the laser gain medium.

[0014] Furthermore, the laser output cavity mirror is coated with a partial reflection film, and the wavelength range of the partial reflection film covers the laser emission spectrum band of the laser gain medium.

[0015] Furthermore, a Q-switching device is provided between the dispersion element and the laser output cavity mirror, and the Q-switching device is located on the laser optical path.

[0016] Furthermore, a Q-switching device is provided between the second reflection grating and the laser output cavity mirror, and the Q-switching device is located on the laser optical path.

[0017] The present invention has the following beneficial effects:

[0018] The present invention changes the optical path of light of different wavelengths emitted by the laser gain medium through a dispersion device, so that light of different wavelengths can be oscillated at different positions of the laser gain medium, thereby enabling the resonant cavity to generate a wide continuous spectrum laser. Compared with a wide spectrum laser using a nonlinear effect, the present invention has a higher conversion efficiency, does not require an ultrashort pulse laser with very high laser peak power as an excitation source, and is low in cost. Moreover, the light source can use an ordinary light source, thereby better controlling the peak power of the laser, making the laser more widely applicable. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 FIG. 4 is a light path diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0020] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] refer to Figure 1A wide continuous spectrum laser comprises a resonant cavity, a pump laser and a laser gain medium, and further comprises: a dispersion element is arranged between the laser gain medium and the laser output cavity mirror, and the dispersion element is located on the laser optical path; the laser gain medium has a wide gain bandwidth.

[0022] Different wavelengths are dispersed to different positions of the gain crystal through the dispersion element to start oscillation.

[0023] In one embodiment of the present invention, the dispersive element is a diffraction grating, a prism, a combination of a diffraction grating and a diffraction grating, a combination of a prism and a prism, or a combination of a diffraction grating and a prism.

[0024] In theory, a single dispersive element can be used. In the preferred solution, it is considered that a single dispersive element will cause chromatic aberration, resulting in large loss of laser light of non-central wavelengths, which is not conducive to the generation of a spectrum. It will also cause different optical parameters when different wavelengths are output.

[0025] In one embodiment of the present invention, the diffraction grating is a reflection grating or a transmission grating.

[0026] In one embodiment of the present invention, the diffraction grating is a planar grating or a non-planar grating or a volume grating.

[0027] In one embodiment of the present invention, the dispersion element includes a first reflection grating and a second reflection grating, the first reflection grating and the second reflection grating are parallel, and the light emitted by the laser gain medium is reflected by the first reflection grating and reaches the second reflection grating, and then reflected by the second reflection grating and reaches the laser output cavity mirror.

[0028] In one embodiment of the present invention, the laser output cavity mirror is a laser output coupling cavity mirror.

[0029] In one embodiment of the present invention, the pump laser performs side pumping or end pumping on the laser gain medium.

[0030] In one embodiment of the present invention, the laser output cavity mirror is coated with a partial reflection film, and the wavelength range of the partial reflection film covers the laser emission spectrum band of the laser gain medium.

[0031] In one embodiment of the present invention, a Q-switching device is provided between the dispersion element and the laser output cavity mirror, and the Q-switching device is located on the laser optical path.

[0032] In one embodiment of the present invention, a Q-switching device is provided between the second reflection grating and the laser output cavity mirror, and the Q-switching device is located on the laser optical path.

[0033] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure made using the contents of the present invention's specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A wide continuous spectrum laser, comprising a resonant cavity, a pump laser and a laser gain medium, characterized in that: Also includes: A dispersion element is arranged between the laser gain medium and the laser output cavity mirror, and the dispersion element is located on the laser optical path; the laser gain medium has a wide gain bandwidth.

2. The wide continuous spectrum solid-state laser transmitter according to claim 1, characterized in that: The dispersive element is a diffraction grating, a prism, a combination of a diffraction grating and a diffraction grating, a combination of a prism and a prism, or a combination of a diffraction grating and a prism.

3. The wide continuous spectrum laser according to claim 2, characterized in that: The diffraction grating is a reflection grating or a transmission grating.

4. The wide continuous spectrum laser according to claim 2, characterized in that: The diffraction grating is a plane grating, a non-plane grating or a volume grating.

5. The wide continuous spectrum laser according to claim 1, characterized in that: The dispersion element includes a first reflection grating and a second reflection grating, the first reflection grating and the second reflection grating are parallel, and the light emitted by the laser gain medium is reflected by the first reflection grating, reaches the second reflection grating, and then reflects by the second reflection grating to reach the laser output cavity mirror.

6. The wide continuous spectrum laser according to claim 5, characterized in that: A Q-switching device is arranged between the second reflection grating and the laser output cavity mirror, and the Q-switching device is located on the laser optical path.

7. The wide continuous spectrum laser according to claim 1, characterized in that: A Q-switching device is arranged between the dispersion element and the laser output cavity mirror, and the Q-switching device is located on the laser optical path.

8. The wide continuous spectrum laser according to claim 1, characterized in that: The laser output cavity mirror is a laser output coupling cavity mirror.

9. The wide continuous spectrum laser according to claim 1, characterized in that: The pump laser performs side pumping or end pumping on the laser gain medium.

10. The wide continuous spectrum laser according to claim 1, characterized in that: The laser output cavity mirror is coated with a partial reflection film, and the wavelength range of the partial reflection film covers the laser emission spectrum band of the laser gain medium.

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