# US 11,079,591 B2 · Method and device for generating a visible image on a projection surface > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,079,591 B2 - Document ID: US11079591B2 - Status: Granted - Kind: B2 - Application number: 16/330,525 - Filed: 2017-07-05 - Published: 2020-07-16 - Granted: 2021-08-03 - Earliest claimed: 2016-09-05 - Assignees: Robert Bosch GmbH - Applicants: Robert Bosch GmbH - Inventors: Frank Fischer; Gael Pilard - Web page: https://patentgrep.com/patent/US11079591B2 ## CPC - G02B 26/101: {with both horizontal and vertical deflecting means, e.g. raster or XY scanners (colour television using laser beams scanning a display screen H04N9/3129)} - 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)} - G03B 21/008: {using micromirror devices} - G03B 21/2033: {LED or laser light sources} - G06F 3/0423: {using sweeping light beams, e.g. using rotating or vibrating mirror} - H04N 9/3164: {using multiple light sources} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - 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) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract A method is described for generating a visible image on a projection surface, in the course of which visible light is emitted from a first laser resonator, the visible light is deflected in the direction of the projection surface with the aid of a deflection element, in particular a micromirror, in order to generate the image, and a light spot of visible light is generated on the deflection element, and invisible light is emitted from a second laser resonator, and a light ring is generated on the deflection element from the invisible light, which enlarges the light spot. ## Claims ### Claim 1 A method for generating a visible image on a projection surface, comprising: emitting visible light from a first laser resonator; deflecting the visible light in a direction of the projection surface with the aid of a deflection element in order to generate the image; generating a light spot of the visible light on the deflection element; emitting invisible light from a second laser resonator; and generating a light ring from the invisible light on the deflection element, the deflection element enlarging the light spot. ### Claim 2 (depends on 1) The method as recited in claim 1, wherein the deflection element includes a micromirror. ### Claim 3 (depends on 1) The method as recited in claim 1, wherein the invisible light emitted from the second laser resonator is imaged onto the deflection element in order to generate the light ring with the aid of an optical element. ### Claim 4 (depends on 3) The method as recited in claim 3, wherein the optical element includes one of a collimation lens provided with a Fresnel ring, a diffractive optical element, and a holographic optical element. ### Claim 5 (depends on 1) The method as recited in claim 1, wherein the light ring and the light spot overlap in an overlap region which has an area that encompasses maximally 5% of an area of the light spot. ### Claim 6 (depends on 1) The method as recited in claim 1, wherein the light ring and the light spot overlap in an overlap region which has an area that encompasses maximally 3% of an area of the light spot. ### Claim 7 (depends on 1) The method as recited in claim 1, wherein the light ring and the light spot overlap in an overlap region which has an area that encompasses maximally 1% of an area of the light spot. ### Claim 8 (depends on 1) The method as recited in claim 1, wherein the invisible light is infrared light. ### Claim 9 (depends on 8) The method as recited in claim 8, wherein the infrared light has a wavelength in a range of 780 nm to 1000 nm. ### Claim 10 (depends on 8) The method as recited in claim 8, wherein the infrared light has a wavelength in a range of 780 nm to 3000 nm. ### Claim 11 (depends on 8) The method as recited in claim 8, wherein the infrared light has a wavelength of 850 nm. ### Claim 12 (depends on 1) The method as recited in claim 1, wherein the invisible light is reflected at the projection surface and detected. ### Claim 13 (depends on 1) The method as recited in claim 1, wherein the visible light is emitted from a plurality of first laser resonators, and wherein light from respective ones of the first laser resonators having different wavelengths. ### Claim 14 (depends on 1) The method as recited in claim 1, wherein: the visible light for generating the image is initially deflected with the aid of a first deflection element, and then with the aid of a second deflection element, and the light spot and the light ring are generated on the first deflection element. ### Claim 15 (depends on 14) The method as recited in claim 14, wherein the first deflection element is a first micromirror. ### Claim 16 (depends on 14) The method as recited in claim 14, wherein the second deflection element is a second micromirror. ### Claim 17 (depends on 1) The method as recited in claim 1, further comprising: ascertaining a distance between the deflection element and the projection surface; and adjusting a radiant power of at least one of the first laser resonator and the second laser resonator as a function of the ascertained distance. ### Claim 18 (depends on 17) The method as recited in claim 17, further comprising: reducing the radiant power if the ascertained distance drops below a predefined minimum distance. ### Claim 19 (depends on 18) The method as recited in claim 18, wherein the radiant power is reduced to zero. ### Claim 20 A device for generating a visible image on a projection surface, comprising: a first laser resonator for emitting visible laser light; a deflection element for deflecting the visible laser light in a direction of the projection surface in order to generate the image, wherein the first laser resonator is aligned in such a way that a light spot is able to be generated on the deflection element from the visible light; and a second laser resonator for emitting invisible light, wherein a light ring is able to be generated from the invisible light on the deflection element, and wherein the deflection element enlarges the light spot. ### Claim 21 (depends on 20) The device as recited in claim 20, wherein the first deflection element is a micromirror.