CN103775976B - Wavelength converter and relevant source system, optical projection system - Google Patents

Abstract

The embodiment of the invention discloses a kind of Wavelength converter and relevant source system, optical projection system, comprising: the first wave length conversion sub-layer of stacked setting and second wave length conversion sub-layer.First wave length conversion sub-layer comprises the incidence surface of second wave length conversion sub-layer dorsad, first wave length conversion sub-layer is for the exciting light that receives from incidence surface incidence and this exciting light is partially converted to Stimulated Light, and part exciting light is transmitted through second wave length conversion sub-layer.The density of the material for transformation of wave length of second wave length conversion sub-layer is greater than the density of the material for transformation of wave length of first wave length conversion sub-layer.Embodiments provide and a kind ofly can improve Wavelength converter to exciting light conversion efficiency and relevant source system, optical projection system.

Description

Wavelength conversion device and related light source system, projection system

technical field

The invention relates to the technical field of illumination and display, in particular to a wavelength conversion device, a related light source system, and a projection system.

Background technique

Currently, wavelength conversion materials are widely used in lighting and display fields. The wavelength conversion material refers to a material that can absorb excitation light of one wavelength to generate light of a different wavelength. The wavelength converting material may be a phosphorescent material, a fluorescent material, a quantum dot, and a mixture comprising at least one of the foregoing.

Fig. 1 is a schematic structural view of a light-emitting device in the prior art. As shown in Fig. 1, the light-emitting device includes an excitation light source 102 and a wavelength conversion layer 101, and the wavelength conversion layer 101 can absorb excitation light 104 emitted from the excitation light source 102, And emit the received light 103 with different wavelengths. The conversion efficiency of the wavelength conversion material can be defined as the ratio of the luminous flux of the subject light 103 to the light power of the excitation light 104 . Generally, the excitation light will be focused onto the surface of the wavelength conversion layer to form a spot. The size of the light spot and the luminous flux of the light emitted from the light spot will determine the brightness of the light emitted by the entire light-emitting device. Generally speaking, the higher the optical power density of the excitation light at the light spot, the more stimulated light will be emitted from the light spot. Assuming that the divergence angle of the subject light 103 remains unchanged, in most cases, the brightness of the subject light 103 will increase as the optical power density of the excitation light 104 increases. However, the conversion efficiency of many wavelength conversion materials will decrease with the increase of the optical power density of the excitation light. This phenomenon is called the saturation effect. Figure 2a is the relationship curve between the intensity of the stimulated light and the optical power density of the excitation light. The big trend is getting slower and slower. Fig. 2b is a relationship curve between the conversion efficiency of the wavelength conversion material and the optical power density of the excitation light. Obviously, the higher the optical power density of the excitation light, the lower the conversion efficiency of the wavelength conversion material.

Contents of the invention

The technical problem mainly solved by the present invention is to provide a wavelength conversion device, a related light source system, and a projection system that can improve the conversion efficiency of excitation light.

An embodiment of the present invention provides a light emitting device, which is characterized in that it includes:

The first wavelength conversion sublayer and the second wavelength conversion sublayer are stacked;

The first wavelength conversion sublayer includes a light incident surface facing away from the second wavelength conversion sublayer, the first wavelength conversion sublayer is used to receive the excitation light incident from the light incident surface and partially convert the excitation light into an accepted light, and Part of the excitation light is transmitted to the second wavelength conversion sublayer;

The density of the wavelength converting material of the second wavelength converting sublayer is greater than the density of the wavelength converting material of the first wavelength converting sublayer.

The present invention also provides a light source system, which includes the above-mentioned wavelength conversion device.

The present invention also provides a projection system, which includes the above-mentioned wavelength conversion device.

Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

In this embodiment, the wavelength conversion material density of the first wavelength conversion sublayer of the wavelength conversion layer is smaller than that of the second wavelength conversion sublayer. Since the density of the first wavelength conversion sublayer becomes smaller, the excitation light absorbed by the first wavelength conversion sublayer is reduced, more excitation light enters the second wavelength conversion sublayer. Therefore, the first wavelength conversion sub-layer with low conversion efficiency reduces the amount of the affected light generated by the second wavelength conversion sub-layer, and increases the amount of the affected light generated by the second wavelength conversion sub-layer. The first wavelength conversion sub-layer reduces the received light, so that the overall efficiency of the wavelength conversion layer is improved.

Description of drawings

FIG. 1 is a schematic structural view of a light emitting device in the prior art;

Fig. 2a is the relationship curve between the intensity of the subject light and the optical power density of the excitation light;

Fig. 2b is the relationship curve between the conversion efficiency of the wavelength conversion material and the optical power density of the excitation light;

FIG. 3 is a schematic structural diagram of an embodiment of a wavelength conversion device in an embodiment of the present invention;

Fig. 4a is a schematic structural diagram of a wavelength conversion layer with uniform distribution of wavelength conversion material density;

Figure 4b is a relationship curve between the incident depth of the excitation light and the optical power density of the excitation light in the wavelength conversion layer of uniform density;

5 is a schematic diagram of the density distribution of the wavelength conversion material of the wavelength conversion layer of another embodiment of the wavelength conversion device in the present invention;

Fig. 6 is a variation curve of the relative optical power density of the excitation light with the increase of the relative depth of the wavelength conversion layer;

FIG. 7 is a schematic structural diagram of the wavelength conversion layer in the prior art and in the embodiment shown in FIG. 3;

8a-8d are density distribution curves of the wavelength conversion layer in another embodiment of the wavelength conversion device of the present invention;

Fig. 9 is a schematic diagram comparing the design curve and the actual curve of the density distribution of the wavelength conversion material of the wavelength conversion layer;

10 is a schematic structural diagram of a wavelength conversion device in another embodiment of the wavelength conversion device of the present invention;

FIG. 11 is a distribution curve of the wavelength conversion material density of the wavelength conversion layer in another embodiment of the wavelength conversion device of the present invention.

detailed description

Embodiments of the present invention will be described in detail below with reference to the drawings and implementation methods.

Embodiment one

Fig. 3 is a schematic structural diagram of an embodiment of a wavelength conversion device in an embodiment of the present invention. As shown in Fig. 3 , the wavelength conversion device 420 only includes a wavelength conversion layer, and the wavelength conversion layer includes a first wavelength conversion sub-layer 421 stacked. and a second wavelength converting sublayer 422 .

The first wavelength conversion sublayer 421 includes a light incident surface 421a facing away from the second wavelength conversion sublayer 422, the first wavelength conversion sublayer 421 receives the excitation light incident from the light incident surface 421a and converts the excitation light part into the accepted light , and transmit part of the excitation light to the second wavelength conversion sub-layer 422 . The density of the wavelength conversion material of the second wavelength conversion sublayer 422 is greater than the density of the wavelength conversion material of the first wavelength conversion sublayer 421 . The most common wavelength conversion material is phosphor, and it can also be a material with wavelength conversion function such as quantum dots or fluorescent dyes.

Figure 4a is a schematic structural view of a wavelength conversion layer with uniform distribution of wavelength conversion material density, as shown in Figure 4a, the wavelength conversion layer 210 receives excitation light 220, and the wavelength conversion material particles 211 of the wavelength conversion layer 210 are evenly distributed in the wavelength conversion layer Inside. When the excitation light is incident into the wavelength conversion layer, the optical power density of the excitation light is significantly reduced due to the scattering and absorption effects of the wavelength conversion material particles 211 . Through experimental detection, Fig. 4b is the relationship curve between the incident depth of the excitation light and the optical power density of the excitation light in the wavelength conversion layer with uniform density. As shown in Fig. 4b, at the 20% depth of the wavelength conversion layer, the excitation light The optical power density of the wavelength conversion layer is only 60% of the excitation light power density on the surface of the wavelength conversion layer, so the excitation light energy density near the incident surface of the wavelength conversion layer is very high and the wavelength conversion material has a high degree of saturation, far from complete absorption The incident excitation light, while the wavelength conversion material particles in the deep layer receive the excitation light with a lower power density, the wavelength conversion material particles in the deep layer will not be saturated. Therefore, for a wavelength conversion layer with a uniform density distribution of wavelength conversion materials, the wavelength conversion material inside receives excitation light with a lower power density, and the conversion efficiency is far from saturation, resulting in lower overall conversion efficiency of the wavelength conversion layer.

In this embodiment, the density of the wavelength conversion material of the first wavelength conversion sublayer 421 of the wavelength conversion layer 420 is smaller than the density of the wavelength conversion material of the second wavelength conversion sublayer 422, because the wavelength conversion of the first wavelength conversion sublayer 421 The density of the material becomes smaller, the excitation light absorbed by the first wavelength conversion sublayer 421 decreases, and more excitation light enters the second wavelength conversion sublayer 422 . Therefore, the amount of the received light generated by the first wavelength conversion sub-layer 421 with low conversion efficiency is reduced, and the amount of the received light generated by the second wavelength conversion sub-layer 422 is increased, because the conversion efficiency of the second wavelength conversion sub-layer 422 is higher than that of The conversion efficiency of the first wavelength conversion sub-layer 421, the amount of light received by the second wavelength conversion sub-layer 422 is more than the number of light received by the first wavelength conversion sub-layer 421, so that the overall efficiency of the wavelength conversion layer is improved. up.

Actually, in order to better improve the conversion efficiency, the wavelength conversion layer may include multiple wavelength conversion sub-layers. Preferably, the wavelength conversion layer may also include a third wavelength conversion sublayer, the first wavelength conversion sublayer, the second wavelength conversion sublayer and the third wavelength conversion sublayer are stacked in sequence, and the wavelength conversion of the third wavelength conversion sublayer The density of the material is greater than the density of the wavelength converting material of the second wavelength converting sub-layer. Compared to the case of two wavelength converting sublayers, the first wavelength converting sublayer of a wavelength converting layer comprising three wavelength converting sublayers absorbs less The excitation light is transmitted to the second wavelength conversion sub-layer and the third wavelength conversion sub-layer, and is absorbed layer by layer, so the efficiency will be higher.

It is easy to understand that the wavelength conversion layer may also be provided with more than three wavelength conversion sub-layers. For example, the wavelength conversion layer of another embodiment of the wavelength conversion device in the present invention can be formed by stacking multiple wavelength conversion sub-layers. The density distribution of the wavelength conversion material in the wavelength conversion layer is shown in Figure 5. Each step Represents the density distribution of a wavelength conversion sublayer, the density of the wavelength conversion material of multiple wavelength conversion sublayers is distributed in a step-like gradient, and the density of the wavelength conversion material increases gradually with increasing depth. The wavelength conversion layer with this structure is also relatively easy to form. Figure 6 is the change curve of the relative optical power density of the excitation light with the increase of the relative depth of the wavelength conversion layer, wherein the solid line part is the change curve of the density of the wavelength conversion layer when the gradient distribution is shown in Figure 5, and the dotted line part is the wavelength conversion When the density of the layer is evenly distributed, the change curves of the two curves are obviously different. For example, at 50% depth, the optical power density of the wavelength conversion layer with uniform density distribution drops to 30% of the surface optical power density, while The optical power density of the wavelength conversion layer with gradient distribution is only reduced to 56% of the surface optical power density. It can be seen that the wavelength conversion material in the deep layer of the wavelength conversion layer with gradient distribution can receive more excitation light than the wavelength conversion layer with uniform distribution. .

In order to further illustrate the working principle of the wavelength conversion device in this embodiment, the prior art is compared with the wavelength conversion device in this embodiment. Figure 7 is a schematic structural view of the wavelength conversion layer in the prior art and the embodiment shown in Figure 3, as shown in Figure 7, the wavelength conversion device A is the wavelength conversion layer in the prior art, including the first wavelength conversion sub-layer a and the second wavelength conversion sublayer b, the wavelength conversion layer B is the wavelength conversion layer in this embodiment, including the first wavelength conversion sublayer c and the second wavelength conversion sublayer d. Here we assume that the density of the wavelength conversion material in the first wavelength conversion sublayer a, the second wavelength conversion sublayer b, and the second wavelength conversion sublayer d is the same, and the density of the wavelength conversion material in the first wavelength conversion sublayer c is the first half of the wavelength conversion sublayer a, and all the wavelength conversion sublayers have the same thickness. When 200 units of excitation light photons are incident on the first wavelength conversion sub-layer a, assuming that 100 units of photons are absorbed, the remaining 100 units of photons will uniformly enter the second wavelength conversion sub-layer b due to scattering or other reasons. If the relative optical power density on the incident surface of the first wavelength conversion sublayer a is 1, according to Figure 6, at the relative depth of 0.5, that is, at the surface of the second wavelength conversion sublayer b, the excitation light of the uniform density wavelength conversion layer The relative optical power density is 0.30. According to Figure 2b, it can be obtained that when the optical power density is 1, the relative conversion efficiency of the first wavelength conversion sublayer a is 0.38, and when the optical power density is 0.30, the relative conversion efficiency of the second wavelength conversion sublayer b is 0.94, so the wavelength conversion can be obtained The received light emitted from layer A is: 0.38×100+0.94×100=132 units. Similarly, for the wavelength conversion layer B, when 200 units of excitation light photons are incident on the first wavelength conversion sublayer c, since the wavelength conversion material density of the first wavelength conversion sublayer c is half of that of the first wavelength conversion sublayer a , 50 units of photons will be absorbed, and the remaining 150 units of photons will be uniformly incident on the second wavelength conversion sub-layer d due to reasons such as scattering. The relative optical power density of the incident surface of the first wavelength conversion sublayer c is also 1. According to FIG. The relative optical power density is 0.56. According to Figure 2b, it can be obtained that the relative conversion efficiency of the first wavelength conversion sublayer c with a relative optical power density of 1 is 0.38, and the relative conversion efficiency of the second wavelength conversion sublayer d with a relative optical power density of 0.56 is 0.88, so It can be obtained that the emitted light of the wavelength conversion layer B is: 0.38×50+0.88×150=141 units, from which it can be seen that the gradient distribution of the wavelength conversion layer has a greater impact on the overall excitation light than the uniform distribution of the wavelength conversion layer. Efficiency has improved.

In addition, because the conversion efficiency of the first wavelength conversion sublayer is low, a large amount of excitation light energy is converted into heat, resulting in a high temperature of the first wavelength conversion sublayer, which reduces the conversion efficiency of the wavelength conversion material. The gradient-distributed wavelength conversion layer converts more excitation light at deeper depths, so the calorific value of the first wavelength conversion sublayer is reduced, which will improve the conversion efficiency of the wavelength conversion material of the first wavelength conversion sublayer, The overall conversion efficiency of the wavelength conversion layer is further improved.

It can be known from experiments that when the excitation light energy absorbed by the first wavelength conversion sublayer and the second wavelength conversion sublayer are relatively close, the overall efficiency of the wavelength conversion layer is higher. Preferably, the density of the wavelength conversion material in the first wavelength conversion sublayer is less than 70% of the density of the wavelength conversion material in the second wavelength conversion sublayer. It has been verified by experiments that the overall conversion efficiency will be significantly improved at this time.

For a wavelength conversion layer composed of multiple wavelength conversion sub-layers with gradient distribution, the density distribution trend may have various forms. Figures 8a-8d are the density distribution curves of the wavelength conversion layer in another embodiment of the wavelength conversion device of the present invention, as shown in Figure 8a, the density of the wavelength conversion layer can increase linearly with the increase of the depth of the wavelength conversion layer . As shown in Figures 8b-8d, the density of the wavelength conversion layer can also increase non-linearly as the depth of the wavelength conversion layer increases. Wherein, the density distribution curve of the wavelength conversion layer shown in Figure 8b is an increasing convex curve, the density distribution curve of the wavelength conversion layer shown in Figure 8c is an increasing concave curve, and the density distribution curve of the wavelength conversion layer shown in Figure 8d is The first half is a convex curve, and the second half is an increasing curve with a concave curve, and different from Figs. 8a-8d, the relative density of the wavelength conversion material on the surface of the wavelength conversion layer shown in Fig. 8d is not zero. Certainly, in the present invention, the relative density of the wavelength conversion material on the surface of the wavelength conversion layer can be set as required. The density distribution curve of the wavelength conversion material of the wavelength conversion layer listed here is only an example of the density distribution of the wavelength conversion material of the wavelength conversion layer of the present invention, and does not constitute a limitation of the present invention. In fact, the density distribution curve of the wavelength conversion material of the wavelength conversion layer of the present invention can have more forms, and the density distribution curve can be determined according to the thickness of the wavelength conversion material layer and the application occasion, so that the wavelength conversion device can be optimized. conversion efficiency.

During the preparation of the wavelength conversion layer, due to process errors and other factors, the density distribution curve of the wavelength conversion material in the wavelength conversion layer cannot completely follow the predetermined design curve, but often includes multiple fluctuations. For example, FIG. 9 is a schematic diagram of the comparison between the design curve and the actual curve of the density distribution of the wavelength conversion material in the wavelength conversion layer. As shown in FIG. 9, the design curve is a linear increasing curve, while the actual curve is distributed around the design curve. There are more undulating curves, but the general density change trend of the design curve and the actual curve is consistent. On the other hand, in the actual manufacturing process of the wavelength conversion layer, the wavelength conversion layer is often composed of multiple wavelength conversion sub-layers, so the density distribution of the wavelength conversion layer may also be discontinuous, forming a stepped gradient distributed. When the thickness of each wavelength conversion sub-layer of the wavelength conversion layer is relatively thin, it can be considered that the density distribution of the wavelength conversion material in the wavelength conversion layer is approximately continuous.

In this embodiment, in addition to the wavelength conversion material, the wavelength conversion layer also includes an adhesive, such as silica gel, PMMA, transparent glass, etc., the adhesive can bond the wavelength conversion material, and the wavelength conversion material can be evenly distributed on the adhesive to form a whole. The adhesive can play the role of fixing the wavelength conversion material, and can isolate the air to protect the wavelength conversion material.

In the present invention, the density distribution curve of the wavelength conversion material in the wavelength conversion layer does not necessarily increase monotonously in the depth direction of the wavelength conversion layer, and may be in other forms. Figure 10 is a schematic structural view of another embodiment of the wavelength conversion device of the present invention, as shown in Figure 10, the wavelength conversion device includes a wavelength conversion layer 520, the wavelength conversion device in this embodiment is the same as the wavelength conversion device shown in Figure 3 The differences between the devices are:

(1) In addition to the first wavelength conversion sublayer 521 and the second wavelength conversion sublayer 522, the wavelength conversion layer 520 in this embodiment also includes a third wavelength conversion sublayer 523 and a fourth wavelength conversion sublayer 524. The density of the wavelength conversion material of the third wavelength conversion sublayer 523 is less than the density of the wavelength conversion material of the second wavelength conversion sublayer 522, and the density of the wavelength conversion material of the fourth wavelength conversion sublayer 524 is greater than the wavelength of the third wavelength conversion sublayer 523 The density of the conversion material, the first wavelength conversion sublayer 521 , the second wavelength conversion sublayer 522 , the third wavelength conversion sublayer 523 and the fourth wavelength conversion sublayer 524 are stacked in sequence. In fact, the wavelength conversion layer in this embodiment is equivalent to the superposition of the wavelength conversion layers in the two embodiments shown in FIG. 3 , so the wavelength conversion layer in this embodiment can also improve the overall conversion efficiency. In addition, when the overall thickness of the wavelength conversion layer is the same, the thickness of the wavelength conversion sub-layer in this embodiment is thinner, so more excitation light will be transmitted through the first wavelength conversion sub-layer and enter the second wavelength conversion sub-layer with higher conversion efficiency. The second wavelength conversion sublayer performs conversion, thereby further improving the conversion efficiency. Preferably, the densities of the wavelength converting materials of the first wavelength converting sublayer and the third wavelength converting sublayer are equal, and the densities of the wavelength converting materials of the second wavelength converting sublayer and the fourth wavelength converting sublayer are equal. The advantage of this is that only two kinds of densities of wavelength conversion sub-layers need to be prepared, which reduces the number of procedures and saves costs.

It is easily conceivable that, in other embodiments of the present invention, the wavelength conversion layer may also have more different wavelength conversion sub-layers whose densities are distributed alternately. For example, the wavelength conversion layer of the wavelength conversion device can be formed by overlapping multiple wavelength conversion sub-layers with different low densities and high densities. The density distribution curve of the wavelength conversion material of the wavelength conversion layer is shown in Figure 11. As the depth increases, the density of the wavelength conversion sub-layers is distributed across high and low. The densities of the different low-density wavelength conversion sub-layers and the high-density wavelength conversion sub-layers here are respectively equal. In other embodiments, the different low-wavelength conversion sub-layers The densities of different high-wavelength conversion sub-layers may also be different.

(2) In the embodiment, the wavelength conversion device further includes a substrate 510, which is in close contact with the surface of the wavelength conversion layer 520 facing away from the light incident surface 521a. Compared with the wavelength conversion layer in which the density of the wavelength conversion material is evenly distributed, the wavelength conversion device in the present invention will generate more heat on the backlight surface of the wavelength conversion layer, and the heat source is close to the substrate, which is conducive to heat conduction. Of course, in other embodiments of the present invention, the substrate can also be omitted if the strength of the wavelength conversion layer is sufficient. In addition, the substrate in this embodiment can be transparent, such as a transparent glass substrate, and the wavelength conversion device is a transmission type at this time; The conversion device is reflective.

(3) In this embodiment, the wavelength conversion device further includes a driving device 530, which can drive the substrate 510 and the wavelength conversion layer 520 to rotate, so that the spot formed by the excitation light on the wavelength conversion layer 520 follows a predetermined path act on the wavelength conversion layer to avoid the temperature rise of the wavelength conversion layer caused by excitation light acting on the same position of the wavelength conversion layer 520 for a long time. Specifically, in this embodiment, the driving device 530 is used to drive the wavelength conversion layer 520 to rotate, so that the light spot formed by the excitation light on the wavelength conversion layer acts on the wavelength conversion layer along a predetermined circular path. Preferably, the substrate 510 is in the shape of a disk, the wavelength conversion layer 520 is in the shape of a ring concentric with the disk, the driving device 530 is a cylindrical motor, and the driving device 530 and the wavelength conversion layer 520 are coaxially fixed. In other embodiments of the present invention, the driving device 530 may also drive the wavelength conversion layer 520 to move in other ways, such as horizontal reciprocating movement. In the case that the wavelength conversion material of the wavelength conversion layer 520 can withstand relatively high temperature, the wavelength conversion device may not be provided with a driving device.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other.

The embodiment of the present invention also provides a light emitting device, the light emitting device includes a laser light source for emitting excitation light, the light emitting device also includes a wavelength conversion device, and the wavelength conversion device may have the structures and functions in the above embodiments.

An embodiment of the present invention also provides a projection system, including a light emitting device, and the light emitting device may have the structures and functions in the above-mentioned embodiments. The projection system may adopt various projection technologies, such as liquid crystal display (LCD, Liquid Crystal Display) projection technology, digital optical processor (DLP, Digital Light Processor) projection technology. In addition, the above-mentioned light-emitting device can also be applied to lighting systems, such as stage lighting.

The above is only the embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process conversion made by using the description of the present invention and the contents of the accompanying drawings, or directly or indirectly used in other related technologies fields, all of which are equally included in the scope of patent protection of the present invention.

Claims (10)

1. a Wavelength converter, comprises wavelength conversion layer, it is characterized in that, described wavelength conversion layer comprises:

The first wave length conversion sub-layer of stacked setting and second wave length conversion sub-layer;

Described first wave length conversion sub-layer comprises the incidence surface of described second wave length conversion sub-layer dorsad, described first wave length conversion sub-layer is for the exciting light that receives from described incidence surface incidence and this exciting light is partially converted to Stimulated Light, and part exciting light is transmitted through second wave length conversion sub-layer;

The density of the material for transformation of wave length of described second wave length conversion sub-layer is greater than the density of the material for transformation of wave length of described first wave length conversion sub-layer.

2. Wavelength converter according to claim 1, is characterized in that: the density of the material for transformation of wave length of described first wave length conversion sub-layer is less than 70% of the density of the material for transformation of wave length of described second wave length conversion sub-layer.

3. Wavelength converter according to claim 1, it is characterized in that: described Wavelength converter also comprises the 3rd wavelength convert sublayer, described first wave length conversion sub-layer, second wave length conversion sub-layer and the 3rd wavelength convert sublayer are cascading, and the density of the material for transformation of wave length of described 3rd wavelength convert sublayer is greater than the density of the material for transformation of wave length of described second wave length conversion sub-layer.

4. Wavelength converter according to claim 3, is characterized in that: the density of the material for transformation of wave length of described first wave length conversion sub-layer, second wave length conversion sub-layer and the 3rd wavelength convert sublayer linearly increases.

5. Wavelength converter according to claim 1, it is characterized in that: described wavelength conversion layer also comprises the 3rd wavelength convert sublayer and the 4th wavelength convert sublayer, the density of the material for transformation of wave length of the 3rd wavelength convert sublayer is less than the density of the material for transformation of wave length of described second wave length conversion sub-layer, the density of the material for transformation of wave length of the 4th wavelength convert sublayer is greater than the density of the material for transformation of wave length of described 3rd wavelength convert sublayer, described first wave length conversion sub-layer, second wave length conversion sub-layer, 3rd wavelength convert sublayer and the 4th wavelength convert sublayer are cascading.

6. Wavelength converter according to claim 5, it is characterized in that: the equal density of the material for transformation of wave length of described first wave length conversion sub-layer and the 3rd wavelength convert sublayer, the equal density of the material for transformation of wave length of described second wave length conversion sub-layer and the 4th wavelength convert sublayer.

7. Wavelength converter according to claim 1, is characterized in that: described wavelength conversion layer also comprises bonding agent, and described bonding agent is used for bonding described material for transformation of wave length.

8. Wavelength converter according to claim 1, is characterized in that: described Wavelength converter also comprises substrate, the intimate surface contact of the described dorsad incidence surface of this substrate and described wavelength conversion layer.

9. a light-source system, is characterized in that, comprises the Wavelength converter according to any one of claim 1 to 8.

10. an optical projection system, is characterized in that, comprises the Wavelength converter according to any one of claim 1 to 8.