CN115657413A - Optical engine technology of three-fold mirror type light band scanning and projector manufactured by same - Google Patents

Abstract

Optical engine technology of three-fold mirror type light band scanning and the manufactured projector; belongs to the technical field of optical electronics, and a core component comprises: display light valve device, lens group, structure supporting assembly, generation assembly of color separation light beam (light band), and continuous crawling type scanning assembly; the continuous crawl-type scanning assembly comprises: the three-fold mirror and the vibrating mirror or the vibrating mirror are not used, and the translation and the vibration of the three-fold mirror are directly realized; the basic working principle is as follows: the continuous crawl type scanning mode comprises the following steps: when the color separation light beam (light band) is projected on the oscillating mirror, the reflected color separation light beam is projected on the three-fold mirror to form a reciprocating projection light spot, the electric control part of the projector converts the image signal into a time sequence pulse for controlling the transmission or reflection light valve pixel on the display light valve device, and the reflectivity of each color light ray of the color separation light beam scanned at the point is selected to reach the target chromaticity and brightness, thereby realizing a color picture; the method is characterized in that: the projector employs a continuous crawl type scanning unit, and the continuous crawl type scanning unit employs a continuous crawl type scanning method.

Description

Optical engine technology of three-fold mirror type light band scanning and projector manufactured by same

[ technical field ]

The invention belongs to the technical field of optics-electronics; it would be exactly one method and apparatus that would enable the optical engines (monolithic LCDs and DLPs) of projectors to greatly enhance brightness.

[ background art ]

The projection technology adopts the combination of a projector and a screen, and the working principle of the projection technology is similar to that of a movie. The projection technology is flexible to use and large in screen size. However, the difficulty of the front projection technology lies in the improvement of the brightness of the projector, especially the loss of most of light energy in the single-chip DLP projection technology and the time-sharing light splitting process.

The core of the projector comprises: the projector mainly comprises three main parts, namely a projector structural component, an optical engine (comprising a lens group), and an electric control interface. The core projection imaging component is the core of the projector product, and occupies a very important part in the cost composition of the whole projector product, and the position of the projection imaging component is similar to a processor in a computer.

The optical engine structure: the development of the projector is now mainly through three development stages, which are realized by three typical display technologies, namely CRT projection technology, LCD projection technology and DLP projection technology developed in recent years.

CRT (Cathode Ray Tube) three-gun projector:

as an imaging device, CRT is one of the earliest and most widely used display technologies. The CRT projector can be said to be a nose-finder of the projector. The CRT projector, also called a three-gun projector, has no difference in its operation principle from the CRT display, and its light source and image are both CRTs. The working characteristics of CRT projector are different from LCD and DLP projectors, it decomposes the input signal source on the fluorescent screen of R (red), G (green) and B (blue) CRT tubes by the self-luminescence, the fluorescent powder emits light under the action of high voltage, amplifies, converges and displays the color image on the large screen. The CRT projector has high resolution, good contrast, good color saturation, strong signal compatibility and mature technology. In terms of brightness, the CRT projector is much lower, so far, the brightness value of the CRT projector always lingers below 300 lumens, meanwhile, the CRT projector is complex to operate, particularly the convergence adjustment is complex, the size of the body is large, and the CRT projector is only suitable for being installed in a relatively fixed place with weak ambient light and is not suitable for being moved. Therefore, although ever prosperous in the early stages of projector market development, CRT projectors are now in few applications, and have substantially exited the front projector market.

LCD (Liquid Crystal Display, liquid Crystal) projector:

LCD display technology is one of the leading technologies in the projector market at present, and liquid crystals include active liquid crystals and inactive liquid crystals. The non-active liquid crystal reflects light and is generally used for notebook computers and film projectors. The active liquid crystal has light transmittance, and can be used in a projector to form an LCD panel. The LCD projector is divided into two types, namely a liquid crystal panel and a liquid crystal light valve, and most of the common projectors are liquid crystal panel projectors. The basic structure of the optical engine of the LCD projection system is provided with a photographic lens; a liquid crystal panel; a mirror; a light-combining prism; a condenser lens; a dichroic mirror; a light bulb.

Liquid crystal (panel) projector:

the liquid crystal projector utilizes the electro-optical effect of liquid crystal and controls the transmissivity and reflectivity of liquid crystal unit via circuit to produce beautiful image with different gray levels and 16.70 million colors. The light source of the liquid crystal panel projector is a special high-power bulb, and the luminous energy is far higher than that of the CRT projector utilizing fluorescence, so that the brightness and the color saturation of the liquid crystal panel projector are both higher than those of the CRT projector. The area of the LCD liquid crystal plate determines the structure and the whole volume of the projector, and the smaller the area of the LCD liquid crystal plate, the smaller the optical system of the projector can be made, thereby the smaller the projector is. Currently, the panel size of liquid crystal projectors (transmissive display light valves) on the market is 1.32 inches (1 inch =2.54 cm), 0.9 inches, and 0.7 inches at most, and the physical resolutions of SVGA and XGA can be supported. New liquid crystal panels, such as 0.79 inch and 0.99 inch panels with high aperture ratio, have also begun to come into the market. High-end LCD projection liquid crystal panel suppliers currently have only two manufacturers, epson and Sony, in japan. The LCD projector has advantages of excellent color representation and high brightness, and has disadvantages in that light efficiency is somewhat affected by the projection method and pixelation occurs in a projected image (aperture ratio is not high enough). Liquid crystal panel projectors can be divided into two types, a single-panel type and a three-panel type, and most modern liquid crystal panel projectors adopt 3-panel type LCD panels. The three-piece liquid crystal board projector uses red, green and blue liquid crystal boards as the control layers of red, green and blue light. The three-chip type liquid crystal panel projector has higher image quality and higher brightness than the single-chip type liquid crystal panel projector. The liquid crystal panel projector has the advantages of small volume, light weight, simple manufacturing process, high brightness and contrast and moderate resolution, and is the projector with the highest share and the most wide application in the current market.

Liquid crystal light valve projector: the liquid crystal light valve projector adopts a CRT tube and a liquid crystal light valve as imaging devices, and is a product of combining the CRT projector and the liquid crystal (reflection) light valve. The projector has the highest brightness and resolution, the brightness can reach 6000ANSI lumens, the resolution is 2500 multiplied by 2000, and the projector is suitable for occasions with strong ambient light and more audiences, such as ultra-large command centers, conference centers and large entertainment venues, but the projector has high price and large volume, and the light valve is not easy to maintain. The main brands are: huss-JVC, ampro, etc.

DLP (Digital Light Processor Digital Light output) Digital projector:

DLP technology is the patented technology of TI (texas instruments, usa). Projectors based on DLP display technology were first introduced in 1996. The imaging Device is a DMD (Digital Micromirror Device). The DMD chip contains thousands of micromirrors, each mirror representing a pixel, the on or off state representing the brightness and darkness of the pixel in the image. The light beam is projected onto the DMD by a color wheel (color separation device) rotating at high speed, and then projected onto a large screen by an optical lens. DLP technology is currently owned by the TI company patent, which is also the only supplier of DMD chips.

Technical advantages of the DLP projector: first is the numerical advantage: the adoption of digital technology has made the image contrast, gray scale (256-1024 levels), color (2563-10243 types), image signal-to-noise ratio, picture quality stable, and the like excellent. Secondly, the reflection advantage: due to the application of the reflective DMD device, the distance between the micro mirror surfaces forming the DLP image pixels is small, and the light transmission efficiency of the imaging device reaches more than 85 percent. The resulting image is very bright and sharp.

DLP projector can be divided into singlechip and three mascerating machines: a single chip microcomputer: the single DLP projector has the advantages of high light efficiency, high contrast, clear image, especially excellent black and white image and text performance, small size, light weight and less color. Three-chip microcomputer: the DLP projector manufactured by using three DMD chips can realize higher brightness and richer colors, the brightness can reach more than 10000ANSI lumens, and the DLP projector is mainly applied to special occasions such as digital cinema and the like.

At present, projectors of LCD technology and DLP technology are two major marketing in the market. The japanese manufacturers mostly adopt LCD technology, and the european and american manufacturers can adopt both LCD and DLP technology. LCD and DLP are in intense competition, whose products and technologies are better, but there is no clear answer at present, but it can be said that the image contrast generated by a projector using DLP is higher, and the optical path system is designed to be more compact, so that it is superior in terms of volume and weight; while LCDs are powerful in terms of brightness uniformity, color, and detail. The two technologies have characteristics and are difficult to distinguish, and coexist in the future for a long time, and unless one party breaks through the technology or the market strategy, the balance is expected to be broken, and the dominant position is occupied.

[ summary of the invention ]

The invention aims to solve the defects of the prior art, namely the single chip type of LCD and DLP technologies, the general efficiency is only about 10 percent, the utilization efficiency of a light source is extremely low, and the main obstacle is that the color generation principle is as follows: the time domain factor of the time sharing process only causes more than 70% of the light energy loss, and the light field is additionally lost for time sharing.

The invention is characterized in that; the coloring defect of time-sharing processing (color wheel switching color) is eliminated in principle, and the technical key of a scanned 'continuously crawling' color separation light beam (short for a light band) is provided to generate color; not only the light energy loss of the generated color separation light beam is small, but also the effective utilization area of the light band is more than 90 percent.

The optical engine structure of the present invention comprises: color separation light beam generating assembly, continuous crawling type scanning assembly, lens assembly and structure supporting assembly; the projector structure using the invention comprises: the projector mainly comprises three main parts, namely a projector structural component, an optical engine (having the 'continuous crawling' characteristic of the invention), an electric control part and an interface.

The core component of the three-fold mirror type optical band scanning technology is realized by a continuous crawling type scanning assembly; the continuous crawl type scanning assembly comprises: the three-fold mirror and the galvanometer or the galvanometer is not used, and the three-fold mirror is directly vibrated (including reciprocating rotation, namely translation and off-axis reciprocating rotation, and the same effect can be achieved when the lens is used for projecting the scanning light band to the display area of the display light valve device); when the color separation light beam (short for light band) is projected on the vibrating mirror, the reflected light band will be projected on the three-fold mirror to form a reciprocating projection light spot (also called as color light band, spectrum or light splitting light beam band); when the projected light spot integrally scans the area of the middle surface of the three-fold mirror, the reflected light spot moves on the display area of the display light valve device, and when the projected light spot integrally crosses the boundary between the middle surface of the three-fold mirror and the edge surface of the three-fold mirror and partially enters the edge surface area of the three-fold mirror (no matter the boundary is crossed towards the direction, the result characteristics are the same because of the symmetrical structure), the reflected light spot entering the edge surface of the three-fold mirror is reflected on the display area at the other end of the display light valve device by the edge surface of the three-fold mirror; when the included angle between the middle surface of the three-fold mirror and the edge surface of the three-fold mirror is determined to meet the following requirements: the reflected light of the light band of the side surface of the three-fold mirror closest to the middle surface of the three-fold mirror is just projected to the edge of the other end of the display area of the display light valve device (which is equivalent to splitting the light band irradiated on the display light valve device into 2 parts, wherein one part is at one end of the display light valve device, the other part is at the other end of the display light valve device, and the two parts can be spliced into a complete color separation beam), which is a 'continuous crawling' process, and the front end of the translational color separation beam projected on the display light valve device is disappeared and displayed at the rear end in appearance; if one characteristic line (on the reference surface) is marked in the band, the entire dichroic beam will fully retrace the display area of the entire display light valve device (i.e., any line of any color in the band represents all of the display area of the display light valve device that is swept by a different color (different wavelengths of light)) when the stroke of the reciprocating motion of the dichroic beam is sufficient so long as the characteristic line (on the reference surface) spans 2 dividing lines; the display light valve device reflects or transmits the light of the moving color separation light beam, then passes through the lens group, and then projects the light to the screen to display an image.

The color separation light beam generation assembly belongs to the prior art: a light source for producing color-separated light beams arranged in order of magnitude and frequency, the light source generating the color-separated light beams includes: a laser light source, a monochromatic light source and a white light source; the shape of the light source is divided into: the light source comprises a surface light source, a point light source, a continuous line light source and a dot matrix line light source; especially, the light efficiency of the line light source is highest, and the heat distribution of the light source is more reasonable (the laser line light source which can be arranged in a dot matrix by adopting a semiconductor laser technology); the method comprises the steps that a multicolor laser light source needs a light-combining prism or a light-combining reflector to combine light beams with various color strip sections, the light beams with various colors are arranged together, and the order of beam expansion and synthesis can be reciprocal; when the multicolor monochromatic light source is used, the light beams with the strip-shaped cross sections of the various colors are combined by using the light-combining prism or the light-combining reflector after being unidirectionally compressed, and are arranged together; the linear light source needs to use a cylindrical curved surface reflector to emit light in parallel, and then uses a light-combining prism or a light-combining reflector to combine light beams with various strip-shaped cross sections and arrange the light beams with various colors together; for a white light source (adopting a semiconductor light emitting technology, a light source in a dot matrix arrangement is available; an arc discharge light source under voltage is also very suitable for a linear light source, and more preferably, if a plurality of fine high-voltage, medium-voltage and low-voltage discharge arcs in a linear arrangement are adopted, the thermal state and the total light emitting quantity of the light source are also greatly improved and improved), a collimated light column with a rectangular cross section is required to be subjected to light splitting (dispersion) treatment: including prism dispersion and color separation grating (which is an interference optical device and replaces prism dispersion to directly form spectrum, but has the defect of large light loss) dispersion, and then the dispersed light is collimated to generate a color separation light beam.

The structure of the optical engine with three-fold mirror type optical band scanning is that the main body is supported by a supporting component to generate the color separation light beam, a continuous crawling type scanning component and a lens group; the working principle of the projector with the three-fold mirror type optical band scanning optical engine correspondingly comprises the following steps: the electric control part of the projector converts the image signal into a time sequence pulse for controlling the transmission or reflection of the light valve pixel on the display light valve device, and selects the reflectivity of each color light of the color separation light beam which scans the point (because the light of each color can scan all the display areas on the display light valve device, the color selection of each pixel point can determine whether to select to pass through the lens when the color scans the pixel), thereby achieving the target chromaticity and brightness and realizing a color picture.

The optical engine of the present invention has the technical improvements that: firstly, the utilization rate of the light source is greatly improved by more than 1 time compared with the prior art; moreover, as the whole color spectrum is laid on the display light valve component without loss, the color is richer, especially in the case of generating the color spectrum for a white light source, because the color spectrum contains the color coordinates of almost all color gamuts, when the light valve pixel modulates the mixed color, the color is closer to the true color. Another technical advance is that: the absolute uniformity of chromaticity and brightness along the scanning direction is brought by the scanning surface, and the uniformity of the light field perpendicular to the scanning direction in the processes of beam expansion and collimation is enough in the design process.

[ description of the drawings ]

The invention will be further described with reference to a preferred embodiment;

FIG. 1 is a schematic diagram showing the formation of a color separation beam (light band).

FIG. 2 is a schematic diagram of the mathematical mechanism for continuation of crawl scanning.

FIG. 3 is a schematic diagram of the necessary dependence of extended crawl scanning on a tri-fold mirror.

FIG. 4 is a schematic diagram of a continuous crawl scanning with simple movement of a triple-fold mirror.

FIG. 5 is a schematic diagram of a continuous crawl scan with a simple dynamic mirror.

FIG. 6 is a schematic diagram of a projector with a triple fold mirror type optical band scanning optical engine.

Description of reference numerals:

(1) Continuous crawl type scanning assembly

(101) The spectrum falls into the middle surface of a three-fold mirror

(102) (103) the spectrum falls into the edge face of the three-fold mirror

(2) Middle surface of three-fold mirror

(3) Edge surface of three-folding mirror

(301) Boundary line of three-fold mirror

(4) Lens group

(5) Color separation beam (section is characterized by spectrum)

(501) Cross section of color separation light beam

(502) Missing spots

(503) (504) filling in the defect light spot

(6) Projecting light

(7) Reflected light

( 8) A display light valve device (liquid crystal transmissive or liquid crystal reflective panel; or DMD reflective chip )

(9) Rotary galvanometer

(904) Translation galvanometer

(901) And (902) direction of displacement

(903) Linear motor

(10) Laser device

(11) Unidirectional beam expanding (cylindrical) lens group

(12) Three-fold mirror

(13) Light-combining prism

(14) Dichroic beam generating assembly

(15) Electric control part

(16) Three-fold mirror

(161) Pendulum vibration three-fold mirror

(162) Three-fold mirror rotating shaft

(163) Direction of shimmy of three-fold mirror

(164) Vertical movement direction of three-fold mirror

(165) (166) vertical displacement of three-fold mirror

(17) Reference surface 1 (perpendicular to the paper surface, represented by a line)

(171) And (172) scanning the sign line

(173) Reference surface 2 (perpendicular to the paper surface, appearing as a line)

(18) Structural shell

(19) Optical engine

(20) Light cross section enlargement

(21) Converging lens

(22) Collimating lens

(23) Section line

(25) Dichroic prism or grating

(26) Curved reflector (column shape: paraboloid, ellipsoid)

(27) Light source

(28) Laser light source

(29) General light source condition

(30) Laser light source (or general light) situation

(31) One-way beam expanding lens

(32) And (33) arrows

(34) (35) Red, blue and green light band

[ detailed description of the invention ]

As shown in [ fig. 1 ]:

the dichroic light beams (bands) are obtained in the following manner:

as shown in the optical path case of the laser light source (or ordinary light) case (30): a laser light source (10) (or a natural light source) is combined through a light combining prism (13), and then expanded through a one-way beam expander (31) to form a red-blue-green light band (34), namely a color separation light beam (light band), wherein the light band is shown as a light section enlarged view (20) of a light beam intercepted by a section line (23) indicated by an arrow (32).

For the white light source case represented by the ordinary light source case (29): the light emitted by the divergent light source (27) is reflected by a curved reflector (26) (columnar: paraboloid, ellipsoid), subjected to color separation by a color separation prism or grating (25) (the light with different wavelengths is separated into different angles), and then arranged near the focal plane by a converging lens (21), and then arranged into color light beams (light bands) by a collimating lens (22). Of course, the light of each color arranged near the focal plane forms already a dichroic beam (light band), and can be used by direct projection.

As shown in [ fig. 2 ]:

a dichroic beam cross-section (501) (the cross-section being characterized by a spectrum) is operatively swept across a display light valve device (8) (the device comprising a liquid crystal transmissive or liquid crystal reflective panel, or DMD reflective chip). In order to enable the spectral lines of each color in each of the color-separated beam sections (501) to sweep across the display light valve device (8), it is necessary to do so in a motion pattern shown by arrow (33) that continues a crawl-like scan: i.e. the reference surface 1 (17) (perpendicular to the paper surface, appearing as a line) must be swept across the entire active display surface of the display light valve device (8); the missing light spots 502 marked by the scanning mark lines 171 and 172 are replenished by the missing light spots 503, and the corresponding missing light spots after the color separation light beam moves to the right are replenished by the missing light spots 504.

As shown in [ fig. 3 ]:

the three-fold mirror configuration is a necessary condition for realizing the mathematical model shown in fig. 2: under the condition that the incident spectrum falls into the middle surface (101) of the three-fold mirror, the reflection spectrum reflected by the middle surface (2) of the three-fold mirror is just projected onto the display effective area of the display light valve device; as the incident spectrum moves up and down, the index lines (173) (i.e., corresponding to the index lines (171) shown in fig. 2) are scanned; a color separation beam (505) (the cross section of which is characterized by a spectrum) crosses a boundary line (301) of the three-fold mirror, so that part of the spectrum is projected onto an edge surface (3) of the three-fold mirror, and because the edge surface (3) of the three-fold mirror and a middle surface (2) of the three-fold mirror form a folding angle smaller than 180 degrees, reflected light rays of the edge surface (3) of the three-fold mirror are just projected onto an effective display area below a display light valve device, which is scanned by the color separation beam; corresponding to the corresponding missing spots shown in fig. 2, from the replenishment of the replenishment spots.

Just as: the spectrum falls under the conditions represented by the three-fold mirror facets (102), (103).

As shown in [ fig. 4 ]:

in addition to the active scanning of the tri-fold mirror by the dichroic beam, the rational self-motion of the tri-fold mirror is the mathematical model shown in fig. 2: the situation of fig. 2 and 3 can be achieved by driving the swing triple-folding mirror (161) to swing along the swing direction (163) of the triple-folding mirror through the rotating shaft (162) of the triple-folding mirror.

In addition: the vertical reciprocating displacement of the three-fold mirror can also reach the situation required by the figures 2 and 3; as shown by the direction of vertical movement (164) of the tri-fold mirror and the positions (165), (166) of vertical movement of the tri-fold mirror.

As shown in [ fig. 5 ]:

the method of obtaining the situation of fig. 2 and 3 is also one of the methods of applying a plane galvanometer to the three-fold mirror to complete the movement of the color splitting beam on the three-fold mirror; the function of the scanning device is completed by a continuous crawling type scanning assembly (1); the rotation of the rotary galvanometer (9) enables the reflected light (7) to move along the displacement direction (901), so that the original projection light (6) overflows the upper part of the display area of the display light valve device and then climbs upwards from the upper part of the display area, and the continuous crawling type scanning motion mode is realized.

In addition; the galvanometer can also be driven by a linear motor (903) to make the mirror surface of the galvanometer perform reciprocating translation to form a translation galvanometer (904); the direction of vibration is as indicated by the double headed arrow. The reflected light thus causes a translation in the direction of displacement (902) to be obtained, as well as a translation in the opposite direction.

As shown in [ fig. 6 ]:

the projector with three-fold mirror type optical band scanning optical engine includes the following structure: an electrical control section (15), a structural housing (18), an optical engine (19); and the optical engine (19) portion is constructed to include: a lens group (4), a display light valve device (8) (a liquid crystal transmission or liquid crystal reflection panel or a DMD reflection chip), a three-fold mirror (16) and a translation vibrating mirror (904).

With a continuous crawl-type scanning assembly that causes the dichroic beam: a motion mode enabling continuous crawl-like scanning; the electric control part of the projector converts the image signal into a time sequence pulse for controlling the transmission or reflection of the light valve pixel on the display light valve device, and selects the reflectivity of each color light of the color separation light beam scanned by the point, thereby achieving the target chromaticity and brightness and realizing a color picture.

Claims (3)

1. Optical engine technique of triple-folding mirror type light band scanning; the components of the projection optical engine technology comprise: display light valve device, lens group, structure supporting assembly, generation assembly of color separation light beam (light band), and continuous crawling type scanning assembly; the continuous crawl-type scanning assembly comprises: the three-fold mirror and the galvanometer or the galvanometer are not used, and the translation and the vibration of the three-fold mirror are directly realized; the basic working principle is as follows: the continuous crawl type scanning mode comprises the following steps: after the color separation light beam (light band) is projected to the galvanometer, the reflected color separation light beam is projected to form a reciprocating projection light spot on the three-fold mirror, or the color separation light beam is directly projected to the three-fold mirror without using the galvanometer, and then a continuous crawling type scanning mode is completed by utilizing the translation and vibration of the three-fold mirror; when the projection light spot integrally scans the area of the middle surface of the three-fold mirror, the reflection light spot moves on the display area of the display light valve device, and when the projection light spot integrally crosses the boundary between the middle surface of the three-fold mirror and the edge surface of the three-fold mirror and partially enters the edge surface area of the three-fold mirror, the reflection light spot entering the edge surface of the three-fold mirror is reflected on the display area at the other end of the display light valve device by the edge surface of the three-fold mirror; the included angle between the middle surface of the three-fold mirror and the edge surface of the three-fold mirror is determined to meet the following requirements: the light band reflected light of the edge surface of the three-fold mirror closest to the middle surface of the three-fold mirror is just projected to the edge of the other end of the display area of the display light valve device; this corresponds to splitting the band of light impinging on the display light valve device into 2 parts: one part is at one end of the display light valve device, the other part is at the other end of the display light valve device, and the two parts can be spliced into a complete color separation beam, which is a 'continuous crawling' process, and the front end of the translational color separation beam projected onto the display light valve device is disappeared and displayed at the rear end; if a characteristic line is marked in the stripe, when the stroke of the dichroic beam to and fro is enough, the whole dichroic beam will fully retrace the display area of the whole display light valve device as long as the characteristic line crosses the boundary line of the 2 three-fold mirrors, that is, the line of any color in the stripe represents all the display areas of the display light valve device which are swept by different colors (different wavelengths of light); the display light valve device reflects or transmits the light of the moving color separation light beam, then the light passes through the lens group, and then the light is projected to a screen to display an image; the method is characterized in that: the present projection optical engine employs a continuous crawl type scanning module, and a continuous crawl type scanning module is used.

2. A projector with a three-fold mirror type optical band scanning optical engine; the core structure includes: an electrical control portion, a structural housing, an optical engine; the core structure of the optical engine comprises: a lens group, a display light valve device and a three-fold mirror; the working principle of the projector comprises the following steps: the electric control part converts the image signal into a time sequence pulse for controlling the transmission or reflection of the light valve pixel on the display light valve device, and selects the reflectivity of each color light ray of the color separation light beam which scans the point; because the light rays with various colors scan all display areas on the display light valve device, the color selection of each pixel point can determine whether to select the pixel through the lens when the color scans the pixel, so that the target chromaticity and brightness are achieved, and a color picture is realized; with a continuous crawl-type scanning assembly that causes the dichroic beam: a motion mode enabling continuous crawl-like scanning; the electric control part of the projector converts the image signal into a time sequence pulse for controlling the transmission or reflection of the light valve pixel on the display light valve device, and selects the reflectivity of each color light of the color separation light beam which scans the point, thereby achieving the target chromaticity and brightness and realizing a color picture; the method is characterized in that: in the projector, a continuous crawl type scanning unit is used, and a continuous crawl type scanning system is used in the continuous crawl type scanning unit.

3. The technology of a projection optical engine with triple-fold mirror type optical band scanning according to claim 1, wherein: the dichroic beam is a dichroic beam arranged in order of magnitude of frequency, and the light source for generating the dichroic beam includes: a laser light source, a monochromatic light source and a white light source; the shape of the light source is divided into: the light source comprises a surface light source, a point light source, a continuous line light source and a dot matrix line light source; especially, the light efficiency of the linear light source is highest, and the heat distribution of the light source is more reasonable; the method comprises the steps that a multicolor laser light source needs a light-combining prism or a light-combining reflector to combine light beams with strip-shaped sections of various colors, the light beams with various colors are arranged together, and the order of beam expansion and synthesis can be reciprocal; when the multicolor monochromatic light source is used, the light beams with the strip-shaped cross sections of the various colors are combined by using the light-combining prism or the light-combining reflector after being unidirectionally compressed, and are arranged together; the linear light source needs to use a cylindrical curved surface reflector to emit light in parallel, and then uses a light-combining prism or a light-combining reflector to combine light beams with various strip-shaped cross sections and arrange the light beams with various colors together; for a white light source, a collimated light column with a rectangular cross section is required to perform light splitting and dispersion treatment: including prism dispersion and color separation grating dispersion, and then the dispersed light is collimated to generate a color separation light beam.

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