Laser light source with adjustable color temperature

Abstract

The utility model discloses a laser light source with adjustable color temperature, comprising a laser diode which emits blue laser with an elliptical light spot; the collimation unit is arranged at the laser end of the laser diode and is used for shaping light spots of a fast axis and a slow axis of the laser, so that the light spots are approximately circular; and the light source processing module is arranged at the other end of the collimation unit and is used for processing a light source of the laser diode. According to the utility model, the light spots of the laser fast and slow axes are shaped and are approximately circular, so that the conversion efficiency of fluorescent powder is higher; light spots are shaped for three times when the laser is emitted from the light outlet of the whole light source, so that the light spots are closer to round light spots required by the market, and the light spot energy is more concentrated.

Description

Technical Field

[0001] The utility model relates to a laser light source, in particular to a laser light source with adjustable color temperature. Background Art

[0002] Generally, laser light sources are divided into transmission laser light sources and reflection laser light sources. Transmission laser light sources have a simple structure and a small overall size, but because the fluorescent material is fixed, the heat dissipation area is small and it is difficult to achieve a high heat dissipation level. They are used for low-power lasers and single lasers.

[0003] The reflective laser light source structure can improve its heat dissipation performance by increasing the heat dissipation area of ​​the fluorescent material to achieve the use of high-power lasers, but the structure has large dimensions, high cost, and limited use environment;

[0004] like Figure 1 As shown, there are two types of laser chips used in laser light sources, namely VSCEL and EEL. The former is mostly used in infrared laser light sources due to the different gain medium materials, while the latter is mostly used in visible light laser light sources. The current EEL laser chip is an edge-emitting laser chip. Due to the rectangular shape of the diode active region, most laser diodes produce elliptical beams with different divergence angles on the fast axis and the slow axis. The fast axis angle is generally much larger than the slow axis angle. Commonly, the fast axis is 20~35° and the slow axis is 7~14°, resulting in an elliptical light spot being emitted.

[0005] The existing technology adds a homogenizing lens or a collimating and focusing component to the light outlet of the light source to shape the laser beam. Generally, only one shaping is performed, and the shaping effect is not ideal. In addition, on the wavelength conversion plate, due to the elliptical light spot, the conversion efficiency of the phosphor is relatively low.

[0006] Existing technologies also have adjustable color temperature. Most of them add a laser diode to control the color temperature of the entire laser light source by controlling the light output of another laser diode. However, the cost is usually higher, and it is easy to cause technical redundancy for those who do not need to adjust the color temperature steplessly. Utility Model Content

[0007] The technical problem to be solved by the utility model is to provide a laser light source with adjustable color temperature to solve the problems existing in the background technology.

[0008] The color temperature adjustable laser light source of the utility model is realized by the following technical solutions, including:

[0009] A laser diode, wherein the laser diode emits a blue laser with an elliptical light spot;

[0010] A collimation unit, which is disposed at the laser end of the laser diode and shapes the laser fast axis and slow axis spots so that the spots are close to a circle;

[0011] A light source processing module is disposed at the other end of the collimating unit to process the light source of the laser diode.

[0012] As a preferred technical solution, the collimation unit includes a fast-axis collimator and a slow-axis collimator;

[0013] The fast axis collimator is located at the laser end of the laser diode, and the slow axis collimator is placed at the other end of the fast axis collimator. The fast axis collimator and the slow axis collimator are on the same axis as the laser diode.

[0014] As a preferred technical solution, the light source processing module includes a dielectric film beam splitter, a first reflector, a second reflector, a dichroic mirror and a wavelength conversion sheet;

[0015] The dielectric film spectrometer is arranged at the other end of the slow axis collimator, and the dielectric film spectrometer is arranged tilted; the center of the dielectric film spectrometer is consistent with the axis of the fast axis collimator and the slow axis collimator, and the dichroic mirror is arranged at the front end of the dielectric film spectrometer and is also located on the axis; the first reflector is arranged at the lower block of the dielectric film spectrometer, the second reflector is arranged below the dichroic mirror, and the positions of the first reflector and the second reflector correspond to each other; the wavelength conversion plate is arranged above the dichroic mirror.

[0016] As a preferred technical solution, it also includes a homogenizing component, and the homogenizing component is arranged at the front end of the dichroic mirror; the rear end of the homogenizing component is installed with a collimating and focusing component.

[0017] As a preferred technical solution, the wavelength conversion sheet includes an anti-reflection film, a phosphor layer, a reflective film and a metal substrate, wherein the reflective film, the phosphor layer and the anti-reflection film are sequentially mounted on the metal substrate.

[0018] As a preferred technical solution, a plurality of dielectric film spectroscopes are provided and mounted in a circumferential direction on a mechanical movable disk for adjusting different color temperatures.

[0019] The beneficial effects of the utility model are:

[0020] 1. The utility model shapes the laser fast and slow axis spot, which is close to a circular spot, so the phosphor conversion efficiency is higher.

[0021] 2. The laser of the utility model performs three light spot shaping when emitting from the entire light source outlet, which is closer to the circular light spot required by the market, and the light spot energy is more concentrated.

[0022] 3. The utility model uses different dielectric film spectroscopes to achieve adjustable color temperature, which is low in cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a structural schematic diagram of the prior art;

[0025] Figure 2 It is a structural schematic diagram of the utility model;

[0026] Figure 3 This is a schematic diagram of the light spot of the utility model;

[0027] Figure 4 This is a schematic diagram of a wavelength conversion sheet of the utility model;

[0028] Figure 5 This is a schematic diagram of the installation of the dielectric film spectroscope of the utility model.

[0029] Description of reference numerals:

[0030] 1. Laser diode; 2. Fast axis collimator; 3. Slow axis collimator; 4. Dielectric film spectrometer; 5. First reflector; 6. Second reflector; 7. Dichroic mirror; 8. Wavelength converter; 9. Homogenizer; 10. Collimation and focusing assembly; 11. Anti-reflection film; 12. Phosphor layer; 13. Reflection film; 14. Metal substrate; 16. Mechanically movable disk. DETAILED DESCRIPTION

[0031] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0032] like Figure 2 As shown, the utility model is a color temperature adjustable laser light source, comprising:

[0033] A laser diode 1, wherein the laser diode 1 emits a blue laser with an elliptical light spot;

[0034] A collimation unit, which is disposed at the laser end of the laser diode 1 and shapes the laser fast axis and slow axis spots so that the spots are close to a circle;

[0035] A light source processing module is disposed at the other end of the collimating unit to process the light source of the laser diode 1 .

[0036] Wherein, the collimation unit includes a fast axis collimator 2 and a slow axis collimator 3;

[0037] The fast axis collimator 2 is located at the laser end of the laser diode 1, and the slow axis collimator 3 is placed at the other end of the fast axis collimator 2, and the fast axis collimator 2 and the slow axis collimator 3 are on the same axis as the laser diode 1; Figure 3 As shown, the fast axis collimator 2 and the slow axis collimator 3 are used to change the shape of the laser beam and collimate the laser. They are essentially the decomposition of the convex lens due to different requirements on the horizontal and vertical axes. The fast axis is focused first, and then another degree of focusing is performed in the slow axis direction, so that the laser beam is closer to a circular spot.

[0038] In addition, the light source processing module includes a dielectric film beam splitter 4, a first reflector 5, a second reflector 6, a dichroic mirror 7 and a wavelength conversion sheet 8;

[0039] The dielectric film spectroscope 4 is arranged at the other end of the slow axis collimator 3, and the dielectric film spectroscope 4 is inclined; the center of the dielectric film spectroscope 4 is consistent with the axis of the fast axis collimator 2 and the slow axis collimator 3, and the dichroic mirror 7 is arranged at the front end of the dielectric film spectroscope 4 and is also located on the axis; the first reflector 5 is arranged at the lower block of the dielectric film spectroscope 4, the second reflector 6 is arranged below the dichroic mirror 7, and the positions of the first reflector 5 and the second reflector 6 correspond; the wavelength conversion plate 8 is arranged above the dichroic mirror 7; the dielectric film spectroscope 4 makes 50% of the incident blue light transmitted and 50% reflected; the transmitted blue light directly reaches the dichroic mirror and almost transmits to the homogenizing component, and the reflected blue light passes through the reflectors 1 and 2, changing the direction of the light from horizontal to vertical, and almost transmits to the wavelength conversion plate on the dichroic mirror to excite yellow light; the yellow light excited in the wavelength conversion plate will be almost completely reflected to the homogenizing component 9 when passing through the dichroic mirror.

[0040] In addition, a homogenizing component 9 is included, and the homogenizing component 9 is arranged at the front end of the dichroic mirror 7; a collimating and focusing component 10 is installed at the rear end of the homogenizing component 9, and the blue light and yellow light passing through the dichroic mirror are mixed into white light after passing through the homogenizing component; the mixed white light will become smaller in angle, rounder in spot, and more concentrated in beam energy after passing through the collimating and focusing component.

[0041] like Figure 4 As shown, the wavelength conversion sheet 8 includes an anti-reflection film 11 , a phosphor layer 12 , a reflective film 13 and a metal substrate 14 , wherein the reflective film 13 , the phosphor layer 12 and the anti-reflection film 11 are sequentially mounted on the metal substrate 14 .

[0042] It is possible to install multiple dielectric film spectroscopes with different reflection and transmission ratios on a mechanical movable disk, such as Figure 5As shown, six dielectric film reflectors are installed on the same mechanical movable disk, that is, the color temperature of the laser light source can be adjusted to six color temperatures, and the adjusted color temperature step and color temperature value can be calculated to determine which reflection-transmission ratio of the spectrometer to use; similarly, according to customer or market needs, other numbers of dielectric film spectrometers with different reflection-transmission ratios can be installed; compared with the current method of adjusting the color temperature of the entire laser light source by adjusting the light output of another laser diode, the utility model will have more advantages in cost.

[0043] The beneficial effects are as follows:

[0044] The utility model adds a homogenizing lens or a collimating and focusing component to the light outlet of the light source, and adds a fast axis collimator (FAC) and a slow axis collimator (SAC) to perform laser shaping before the light emitted by the laser chip reaches the wavelength conversion plate. On the wavelength conversion plate, since the light spot is close to a circular spot, the phosphor conversion efficiency will be relatively higher; and the utility model can achieve two light spot shaping when the laser is emitted from the entire light outlet of the light source, which is closer to the circular spot required by the market.

[0045] The utility model adopts spectroscopes with different dielectric films to control the proportion of blue light used for mixing and for exciting fluorescent powder of a single laser diode to achieve adjustable color temperature with low cost.

[0046] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any changes or substitutions that are not conceived through creative work should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope defined in the claims.

Claims

1. A color temperature adjustable laser light source, characterized in that: include: A laser diode (1), the laser diode (1) emitting blue laser light, and the light spot is elliptical; A collimating unit, which is arranged at the laser end of the laser diode (1) and shapes the laser fast axis and slow axis light spots so that the light spots are close to a circle; A light source processing module, which is disposed at the other end of the collimating unit and processes the light source of the laser diode (1); The collimation unit comprises a fast-axis collimation mirror (2) and a slow-axis collimation mirror (3); The fast axis collimator (2) is located at the laser end of the laser diode (1), the slow axis collimator (3) is located at the other end of the fast axis collimator (2), and the fast axis collimator (2) and the slow axis collimator (3) are located on the same axis as the laser diode (1).

2. The color temperature tunable laser light source according to claim 1, characterized in that: The light source processing module comprises a dielectric film beam splitter (4), a first reflector (5), a second reflector (6), a dichroic mirror (7), and a wavelength conversion plate (8); The dielectric film beam splitter (4) is arranged at the other end of the slow axis collimator (3), and the dielectric film beam splitter (4) is arranged at an angle; the center of the dielectric film beam splitter (4) is consistent with the axis of the fast axis collimator (2) and the slow axis collimator (3), and the dichroic mirror (7) is arranged at the front end of the dielectric film beam splitter (4) and is also located on the axis; the first reflector (5) is arranged at the lower block of the dielectric film beam splitter (4), the second reflector (6) is arranged below the dichroic mirror (7), and the positions of the first reflector (5) and the second reflector (6) correspond to each other; the wavelength conversion plate (8) is arranged above the dichroic mirror (7).

3. The color temperature tunable laser light source according to claim 1, characterized in that: It also includes a homogenizing component (9), and the homogenizing component (9) is arranged at the front end of the dichroic mirror (7); and a collimating and focusing component (10) is installed at the rear end of the homogenizing component (9).

4. The color temperature tunable laser light source according to claim 2, characterized in that: The wavelength conversion sheet (8) comprises an anti-reflection film (11), a phosphor layer (12), a reflective film (13) and a metal substrate (14); the reflective film (13), the phosphor layer (12) and the anti-reflection film (11) are sequentially mounted on the metal substrate (14).

5. The color temperature tunable laser light source according to claim 2, characterized in that: The dielectric film spectroscope (4) is provided in multiple pieces and is mounted on a mechanical movable disk (16) in a circumferential direction for adjusting different color temperatures.

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