EP1886180A1

EP1886180A1 - Frequency-addressing matrix routing head for light beams

Info

Publication number: EP1886180A1
Application number: EP06764603A
Authority: EP
Inventors: Jean-Marc Desaulniers; Gaëtan ROTTIER
Original assignee: Breizhtech Sas
Current assignee: BREIZHTECH SAS
Priority date: 2005-05-24
Filing date: 2006-05-11
Publication date: 2008-02-13
Also published as: JP2008542803A; WO2006125881A1; AU2006251075A1; ZA200710789B; KR20080019588A; NZ563646A; TNSN07454A1; BRPI0611529A2; RU2403600C2; RU2007142827A; MA29556B1; US20080231929A1; CN101203792A; CA2609159A1; CN101203792B; FR2886416A1; HK1122361A1

Abstract

The invention relates to a device (FIG. 1) for the generation of a light beam matrix (1), supplying for example, the output stage of a digital video projector, by means of a combination of light sources (2), (3) and (4) of weak to moderate power for the three base colours (red, green and blue), of the laser or xenon source type and n x m mirrors (5) of a given size and shape defined as a function of the target application, carrying out the corresponding frequency filtering as a function of the construction of the mirror. The device comprises a number of matrices (6), (7), (8) and (9) of mirror/filters aligned geometrically, for orientation and filtering of the light beams (10) in order to generate a matrix/symbol projection element (1). The device avoids a sweeping function as a result of frequency coding for the position of each projected matrix element. The digital control permits the control of the operation of the light sources as a function of the matrix/symbol display required at a given time t . Said matrix/symbol element is swept across a projection surface in order to generate a complex video image sequence. The system is of application to, for example, top of the range digital cinema and home cinema equipment.

Description

Matrix routing light beams frequency addressing head The present invention relates to a device to attack, using a matrix of light beams on the last floor of a 2 ^nd generation video projector for digital cinema, for large-screen projection of an ultra-high-definition RGB video signal using as a light source a low / medium power laser or generated white light, e.g. ex. by a xenon lamp of very high intensity. The flexibility of the spatial and frequency optical device allows its application in the field of telecommunications (eg router, wavelength multiplexer / demultiplexer, switchman, coupler, polarization analyzer, ...).

Projection in cinemas is traditionally done using a 35mm or 70mm film projector. There are a number of implementations, based on DLP or LCD technology, that can achieve a resolution of 2K x IK, as well as a prototype, based on GLV technology, supporting 2K x 4K pixels. The use of these technologies applied at high resolutions, induces exponential costs related to the development of basic components (DLP, GLV and LCD matrix). The use of microscopic metal components (micro-mirrors DMD for DLP technology and micro-lamellae for GLV), induces problems of residual magnetic field, resonance, aging (due to multiple and repeated twists), oxidation as well as a limitation on the maximum beat / refresh rate that can be achieved. At the LCD level the main problems lie in the use; 1) dichroic filters inducing transmission losses and distortion of the basic color components (RGB mix, range and temperature) at the reconstructed light signal, 2) LCD shutter matrices having a maximum activation frequency / deactivation (shutter cycle) limited. These combined effects make it difficult to optimize the mix / temperature pair of the color with a sufficient level of contrast, required by moviegoers. The field of application is very high-end Digital Cinema oriented initially, and can be re-applied to other market segments (eg the "Home Cinema") once the level of integration (reduction in the size of the mechanism) and industrialization costs have been sufficiently optimized.

The device according to the invention makes it possible to reproduce, on a projection screen of variable size and shape, a sequence of Ultra High Definition (UHD) color images, using a light source, by means of a head Frequency addressing light beam routing matrix. The challenge is to preserve at the output the intrinsic characteristics of the original signal (range, mix, color temperature, resolution / definition, contrast level, ...). Video projection by an almost entirely optical device (light beam + mirrors / filters) is optimized because it involves only a series of reflections / transmissions on mirrors / filters, which ultimately will undergo only a very small surface mechanical wear.

This device makes it possible to generate a matrix light beam (1), using a combination of light sources, eg (2), (3) and (4) of low / medium power, supporting p. ex. the three basic colors (red, green and blue), laser type or white light source filtered or not, and "n" x "m" mirrors (5) of a certain size and shape defined in function the intended application, performing appropriate filtering, arising from the construction of the mirror / filter. The device comprises a number of arrays, eg (6), (7), (8) and (9) of geometrically aligned mirrors / filters orienting and filtering the light beams (10) for the purpose of generating an element. matrix / symbol (1) projection. The device eliminates a scanning function by frequency coding the position of each matrix element. The digital control makes it possible to control the lighting of the light sources according to the configuration of the matrix / display symbol sought at a given instant "t". This matrix / symbol element will be scanned on a projection surface to generate a complex video image sequence.

The operating principle involves the matrix scanning of light beams over a given area (eg part of a projection screen), by inserting a frequency comb corresponding to a specific part of the spectrum to which a light beam is applied. certain number of reflections / transmissions, through a matrix arrangement of mirrors / filters. The beam will have a diameter that will be within a range of about 0.03 mm to 10 mm (to be determined depending on the intended applications) at the output of the projection block. Instead of using a traditional spatial and temporal scanning of a screen area, a frequency scanning technique is employed through mirrors / filters covered with a thin metallized layer, making it possible to reflect and / or transmit a light beam on a matrix display surface. Each comb consisting of a certain number of frequencies, depending on the structure of the target matrix (n × m), makes it possible to code the output matrix symbol. The pulse frequency of the combs represents the refresh period of all the points of the matrix made simultaneously. On each of the frequencies the intensity modulation represents the refresh period of each pixel. The input comb encounters a succession of mirrors / filters which, according to their characteristics, transmit one part of the spectrum and reflect the other. The succession of mirrors / elementary filters therefore allows a matrix geometric distribution of the incident beam.

According to the particular embodiments: The device (FIG.1) is illuminated by a discrete or continuous light spectrum. Depending on the intended application, the mirrors / filters may have identical characteristics or not. A set of mirrors / filters having identical frequency characteristics but a variable pitch of the transmission / reflection ratio makes it possible to create a matrix of "n" x "m" light beams from a point source.

A set of mirrors / filters having identical transmission / reflection rates but variable pitch frequency characteristics allow the device to behave as a frequency demultiplexer multiplexer according to the direction of light travel. The accompanying drawings illustrate the invention:

Figure 1 represents a perspective of the complete device of the invention.

Figure 2 shows, in section, a mirror / elementary filter. FIG. 3 represents in section a succession of elementary mirrors / filters constituting part of a row or column of a stage of the matrix.

Figure 4 shows a perspective of the lower stage of the matrix.

Figure 5 shows a perspective of one of the upper stages of the matrix.

FIG. 6 represents a section of a portion of the upper stages of the matrix allowing the division and the spectral and spatial recombination of each pixel.

FIG. 7 represents the sectional view of a variant of the device made with a set of sources distributed around an axis, composed for example of one or more crowns of increasing and superposed sizes accommodating a certain number of mirrors. filters.

FIG. 8 represents the front view of a variant of the device made with a source assembly distributed around an axis composed of several mirror / filter rings.

Figure 9 shows a front view of the mirror crowns / filters of the variant.

FIG. 10 represents a front view of the mirror / filter matrices of the variant, arranged in the form of a pyramid, eg on three stages of increasing accommodating surfaces, eg 4, 12 and

20 mirrors / filters. Fig. 11 shows one of the mirrors / filters of the device inclined, eg at 45 degrees.

With reference to these drawings, the device (FIG. 1) comprises a series of lower and upper stages composed of a certain number of mirrors / filters defined as a function of

F applications targeted.

The elementary component, mirrors / filters (FIG 2) consists of a prism or a blade covered with a treatment. Depending on the intended application, this processing makes it possible to transmit or reflect a proportion (eg a portion of intensity, a spectral portion of the polarization, ... or any combination) of the characteristics of the incident beam. According to the production techniques, the elementary mirror / filter component is integrated in the mass of the device or is deposited on the surface. The sequence of "m" filters / mirrors (FIG 3) for a succession of selective mirrors in wavelengths, for example, makes it possible to spatially separate the beam incident (10) in "m" beams of different spectral components (12), (13) and (14). Each of the spectral components is determined by the characteristics of the mirrors / filters during their construction.

The lower stage (FIG 4) has a succession of "m" elementary mirrors / filters on "p" lines (eg three lines representing the three RGB base colors). Each of these aligned surfaces makes it possible to spatially address one of the "m" columns of "n" aligned surfaces of an upper stage (FIG. The lower matrix therefore addresses a column of the array of beams leaving the device.

The upper stages realize, as shown for example in FIG. 6 for mirrors / filters selective in wavelengths, the selection of the position of the beam on the column thanks to a succession of mirrors / filters (15), (16) and (17). The superposition of the "p" upper stages allows the recomposition of the spectrum of each beam (18) and (19) composing the output matrix of the device (eg the RGB component of each pixel of the matrix). Depending on the configuration and the intended application, because of its reversibility, the device may be used not only to obtain a particular array of beams from a single or multiple incident beams (eg the simultaneous generation of a RGB pixel array representing an image from a frequency encoding of the information), but also to generate one or more beams from an incident beam array (eg generating a frequency coding of 'a picture).

Other implementation variants, the device (FIG 7) for generating a matrix laser beam supplying the last stage of a digital video projection equipment, using a combination of low / medium power laser source supporting the three basic colors (red, green and blue), and a mirror prism. The device comprises a number of rings (20) accommodating the laser heads (21) oriented towards the center of the latter (FIG 8), where the mirrors / filters (FIG 11) are located to align each of the laser beams for the purpose of generating a projection matrix / symbol element (22). The mirrors / filters are arranged on a certain number of rings (FIG 9) rotating or not in ways to generate the desired array of light beams. A numerical control will control the ignition of the laser heads according to the configuration of the matrix / symbol sought at a given instant "t". This matrix / symbol element will be scanned on a projection surface for generating a complex video image sequence. The system will initially be applied to the very high end Digital Cinema and then to the "Home Cinema".

Claims

1) Device (FIG.1) for creating a matrix flow of collinear collinear light beams, or made collinear from a number of collimated beams, making it possible to perform the digital projection video of a matrix of pixels (1 ), by means of a number of light beams from one or more sources, eg (2), (3) and (4) of the laser or white light type, and this by reflections / transmissions successive on mirrors / filters (11) having a geometric alignment of matrix type.

2) Device (FIG 1) according to claim 1 showing a matrix structure of passive optical elements characterized by an alignment of the inclined mirrors / filters (11) distributed over 1 to "x" stages, eg 6), (7), (8) and (9), making it possible to generate, by a series of successive reflections / transmissions (FIG-3) and (FIG.6), the simultaneous scanning of a matrix of points or collimated beams collinear (1), thanks to a frequency and spatial coding of each of the elementary pixels inside the matrix of light beams. The surfaces coated with a very thin metallized layer having specific filtering properties will be able to form, from an input frequency comb, a matrix of beams at the output of the 1 to "x" upper stages of the matrix, eg (6), (7) and (8), eg each position corresponding to a specific frequency signature of the input signal.

3) Device (FIG.l) according to claims 1 and 2, characterized in that the sources, eg (2), (3) and (4), allow to generate a pulsed frequency comb, discrete or continuous circuit (10), wherein each of the constituent frequencies is amplitude modulated, within a beam associated with one of the pixels of a dot matrix, with a period for generating a video image sequence. Each comb (10) consisting of a certain number of frequencies, resulting from the structure of the target matrix (FIG 4) and / or (FIG 5), makes it possible to code the output matrix symbol. Each point of the output matrix symbol corresponding to a specific part of the spectrum.

4) Device (FIG 1) according to claims 1 to 3 characterized in that it is composed of lower stages (FIG 4) and higher (FIG.5) forming a matrix distribution of elements (FIG 11) allowing reflection, transmission and / or filtering (FIG 2) of the incident beam passively according to one or more of its physical characteristics. For example, the particular cutoff frequency imposed by the structure of the metal surface, specific to each of the facets, itself a function of its position in the matrix group, eg (6), (7), (8) ) and (9). 5) Device (EIG 1) according to claims 1 to 4 characterized in that it is used in the opposite direction, the component is bidirectional, allowing to recombine / passively code a matrix of beams (1) from the physical characteristics associated with one or more beams, eg (2), (3) and (4), by encoding the physical position of each of the beams within the input matrix (1). This device makes it possible, for example, to perform a frequency multiplexing function by recombination, in the form of a comb, of the different frequencies specific to the incident beams distributed in space.

6) Device (FlG.7) according to claim 1, characterized in that it represents a variant embodiment of a matrix of light beams (22) using a combination of rings (EIG.8) integrating a number of sources (21) oriented towards the center of each ring, having a number of stages of crowns (FIG 9) or pyramids (FIG 10) rotating or not, on which are distributed a number mirror / filter elements (FIG.11) inclined at an angle (26) for normal reflection (27) with respect to the device (FIG.7) and (FIG.8). 7) Device (FIG.11) of mirrors / filters which may, for example, be arranged geometrically, eg to be successively traversed by a number of light beams, according to claims 1 to 6, characterized in that they allow the reflection and / or the progressive filtering in a specific way to the intended application, eg with a decreasing wavelength decreasing in steps, eg in the nanometer range, and a plurality of incident beams (10) on the surface (11) or in the mass (23), the mirror / filter device being in the mass or deposited on the surface of the device (FIG. (FIG 4) and (FIG-5), and the device (FIG 7) incorporating the devices (FIG 8) and (FIG.9) or (FIG 10), this element does not change the collimation or the a number of incident beams.