# US 2014/0152961 A1 · Laser module and scanner projector > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0152961 A1 - Document ID: US20140152961A1 - Status: Published application - Kind: A1 - Application number: 14/097,969 - Filed: 2013-12-05 - Published: 2014-06-05 - Earliest claimed: 2012-12-05 - Assignees: Robert Bosch GmbH - Inventors: Gael PILARD - Web page: https://patentgrep.com/patent/US20140152961A1 ## CPC - G03B 21/2073: {Polarisers in the lamp house (peculiar to electronic spatial light modulators H04N9/3197)} - G02B 27/28: for polarising (used in stereoscopes G02B30/25) - G02B 27/283: {used for beam splitting or combining} - G02B 27/4261: {having a diffractive element with major polarization dependent properties} - G02B 27/48: Laser speckle optics - G03B 21/2033: {LED or laser light sources} - G03B 21/2066: {Reflectors in illumination beam (in projection beam G03B21/28)} - G03B 33/12: using beam-splitting or beam-combining systems, e.g. dichroic mirrors - H04N 1/0282: {Using a single or a few point light sources, e.g. a laser diode} - H04N 9/3129: {scanning a light beam on the display screen (scanning a light beam on a screen in displays other than projection devices G09G3/02; scanning systems in general G02B26/10; projectors using laser light sources in general H04N9/3161)} - H04N 9/3161: {using laser light sources (using laser beams scanning the display screen H04N9/3129)} - H04N 9/3167: {for polarizing the light beam (polarizing optical systems per se G02B27/28)} - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A laser module includes a first laser light source, a second laser light source, and a third laser light source. Laser beams of the laser light sources are combinable into an overall laser beam. The laser beam of the first laser light source and the laser beam of the second laser light source have a first polarization, and the laser beam of the third laser light source has a second polarization. The laser beams of the first and the third laser light sources are coupled into the overall laser beam with the aid of mirror devices. The laser beam of the second laser light source is split, the polarization of the laser beam of the second laser light source being changed from the first polarization to the second polarization in a splitting path. The laser beam of the second laser light source having the second polarization is coupled into the overall laser beam via the splitting path, and the laser beam of the second laser light source having the first polarization is coupled into the overall laser beam via a main path. ## Claims ### Claim 1 A laser module, comprising: a first laser light source; a second laser light source; and a third laser light source, wherein: laser beams of the first, second, and third laser light sources are combinable to form an overall laser beam, the laser beam of the first laser light source and the laser beam of the second laser light source have a first polarization, and the laser beam of the third laser light source has a second polarization, the laser beams of the first and the third laser light sources are coupled into the overall laser beam with the aid of mirror devices, the laser beam of the second laser light source is split, the first polarization of the laser beam of the second laser light source is changed from the first polarization to the second polarization in a splitting path, the laser beam of the second laser light source having the second polarization is coupled into the overall laser beam via the splitting path, and the laser beam of the second laser light source having the first polarization is coupled into the overall laser beam via a main path. ### Claim 2 (depends on 1) The laser module as recited in claim 1, wherein: the laser beam of the first laser light source is reflected by essentially 90 degrees with the aid of a 50/50 beam splitter which has a surface, facing the first laser light source, having a wavelength-dependent coating which is totally reflective for the first laser light source, the reflected laser beam of the first laser light source is coupled into the overall laser beam, the laser beam of the second laser light source is split into the main path and the splitting path with the aid of the 50/50 beam splitter. ### Claim 3 (depends on 1) The laser module as recited in claim 1, wherein: the change in the polarization of the second laser beam of the second laser light source is carried out using a lambda/2 plate, an orientation of the lambda/2 plate relative to a polarization direction of the laser beam of the second laser light source is approximately 45 degrees. ### Claim 4 (depends on 1) The laser module as recited in claim 1, wherein: the laser beam of the first laser light source is deflected by essentially 90 degrees with the aid of a wavelength-dependent coating of a first polarization-dependent beam splitter and is coupled into the overall laser beam, the polarization of the laser beam of the second laser light source is changed from the first to the second polarization with the aid of the first polarization-dependent beam splitter, the laser beam of the second laser light source is split into the main path and the splitting path, a portion of the laser beam having the first polarization of the second laser light source is coupled into the main path, and a portion of the laser beam having the second polarization of the second laser light source is coupled into the splitting path. ### Claim 5 (depends on 4) The laser module as recited in claim 4, wherein the laser beam of the second laser light source has a first polarization having an orientation of essentially 45 degrees with respect to the first polarization-dependent beam splitter. ### Claim 6 (depends on 1) The laser module as recited in claim 1, wherein: the laser beam of the third laser light source is coupled into the splitting path of the laser beam of the second laser light source with the aid of a second mirror device which has a surface, facing the third laser light source, having a coating which is transparent to the laser beam of the third laser light source, and the laser beam of the second laser light source having the second polarization is reflected by essentially 90 degrees with the aid of the second mirror device. ### Claim 7 (depends on 1) The laser module as recited in claim 1, wherein tolerances of at least one element from a group including a 50/50 beam splitter, a first polarization-dependent beam splitter, a first mirror device, a lambda/2 plate, a second mirror device, and a second polarization-dependent beam splitter, are dimensioned in such a way that an angle between the combined laser beams of the three laser light sources is minimal. ### Claim 8 (depends on 6) The laser module as recited in claim 6, wherein two mirror devices are situated in the splitting path, at least one of the mirror devices being mechanically adjustable. ### Claim 9 (depends on 1) The laser module as recited in claim 1, wherein the first laser light source is a blue laser diode, the second laser light source is a red laser diode, and the third laser light source is a green laser diode. ### Claim 10 (depends on 1) The laser module as recited in claim 1, wherein the first polarization is a linear polarization and the second polarization is a vertical polarization. ### Claim 11 A scanner projector, comprising: a laser module, comprising: a first laser light source; a second laser light source; and a third laser light source, wherein: laser beams of the first, second, and third laser light sources are combinable to form an overall laser beam, the laser beam of the first laser light source and the laser beam of the second laser light source have a first polarization, and the laser beam of the third laser light source has a second polarization, the laser beams of the first and the third laser light sources are coupled into the overall laser beam with the aid of mirror devices, the laser beam of the second laser light source is split, the first polarization of the laser beam of the second laser light source is changed from the first polarization to the second polarization in a splitting path, the laser beam of the second laser light source having the second polarization is coupled into the overall laser beam via the splitting path, and the laser beam of the second laser light source having the first polarization is coupled into the overall laser beam via a main path. ### Claim 12 A method for generating an overall laser beam from multiple laser beams, comprising: emitting a laser beam in each case from a different laser light source; coupling a laser beam of a first laser light source having a first polarization into the overall laser beam; coupling a laser beam of a third laser light source having a second polarization into the overall laser beam; splitting a laser beam of the second laser light source having the first polarization into a main path and a splitting path, in the splitting path the first polarization of the laser beam of the second laser light source being changed from the first polarization to the second polarization; and coupling the laser beam of the second laser light source into the overall laser beam via the main path and via the splitting path.