CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No. PCT/CN2017/114736, filed on Dec. 6, 2017, which claims priority to and the benefit of CN 201710735960.6, filed on Aug. 24, 2017. The disclosures of the above applications are incorporated herein by reference.

FIELD

The present disclosure relates to the field of projection display and, particularly, to a light source system and a projection system using the light source system.

BACKGROUND

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

At present, a scheme of a light source form of blue light+yellow light (Y+B) is generally applied to a three-piece spatial light modulator (3SLM) system or a two-piece spatial light modulator (2SLM) system, but these systems have large structures, complicated manufacturing processes, and high prices. In a single spatial light modulator system, since the efficiency of red phosphor is much lower than the efficiency of red light intercepted from yellow fluorescent light, when applying the light source form of Y+B to the single spatial light modulator system, it is necessary to decompose the yellow light (Y) to obtain green light (G) & red light (R), and R is lost by reflection when G is obtained and G is lost by reflection when R is obtained, which causes a low efficiency.

In an existing single spatial light modulator projection system, taking digital light processing (DLP) technology as an example, as shown inFIG. 1, the single spatial light modulator projection system includes an excitation light source101, a wavelength conversion device102, a filter wheel103, a light relay system104, a light homogenizing device105, and a digital micromirror device (DMD) chip106, and a total internal reflection (TIR) prism107.

The excitation light source101emits excitation light to excite the rotating wavelength conversion device102to generate excited illumination light that is in a time sequence, and the filter wheel103is synchronized with the wavelength conversion device102and filters the illumination light. The filtered illumination light is homogenized by the light homogenizing device105and totally reflected at the TIR prism107to irradiate the DMD chip106. The DMD chip106receives image signals and modulates the illumination light to form image light. Then the image light is emitted to a projection lens (not shown) via the TIR prism107.

Surface structures of the wavelength conversion device102and the filter wheel103are as shown inFIG. 2. The excitation light excites the wavelength conversion device102to generate sequence light of B+Y, which is then filtered by the filter wheel103to form sequence light of blue light+red light+green light (B+R+G). As shown inFIG. 3, an emission spectrum of Y covers spectral regions of R and G, so R light and G light can be intercepted from the Y spectrum. When the filter wheel103rotates to a G filter region, R light is lost by reflection, and when the filter wheel103rotates to an R filter region, G light will be lost by reflection, and it can be seen fromFIG. 3that luminous flux lost from G light occupies most of the Y light, about 80%. Therefore, in the current technology, the lost luminous flux is relatively high, and the light efficiency of the system is relatively low.

SUMMARY

This section provides a general summary of the disclosure and is not a comprehensive disclosure of its full scope or all of its features.

In view of the above, the present disclosure provides a projection system with a high light energy utilization efficiency.

The present disclosure provides a projection system, including:

a light-emitting device configured to provide first light and second light that are to be emitted in time sequences;

a light-splitting system comprising:

a light-splitting device configured to split the first light into first primary color light and second primary color light, split the second light into two paths of third primary color light, emit the first primary color light along a first optical path and the second primary color light along a second optical path in a first time sequence, emit the first primary color light along the second optical path and the second primary color light along the first optical path in a second time sequence, and emit the two paths of third primary color light respectively along the first optical path and the second optical path in a third time sequence;

a spatial light modulator comprising at least a first region and a second region, wherein the first primary color light, the second primary color light, and the third primary color light that are emitted along the first optical path according to the first time sequence, the second time sequence, and the third time sequence enter the first region and are modulated by the first region into image light to be emitted, and the second primary color light, the first primary color light, and the third primary color light that are emitted along the second optical path according to the first time sequence, the second time sequence, and the third time sequence enter the second region and are modulated by the second region into image light to be emitted; and

an image processing device configured to divide image signals to be outputted to the spatial light modulator into two groups corresponding to the first region and the second region, and change a sequence of at least one of the two groups of image signals to match time sequences according to which a region corresponding to the at least one group of image signals receives the first primary color light, the second primary color light, and the third primary color light.

Advantages of the projection system provided by the embodiments of the present disclosure lie in that at least two light channels are provided, and a single spatial light modulator can modulate at least two beams of incident light at the same time. In this way, the reflected light can be recovered to avoid light loss occurring when the light-splitting device splits light, thereby improving the light energy utilization efficiency. Moreover, the projection system has a relatively small structure volume and a relatively low cost.

Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

