Method and system for selectively adjusting pixels, in an optical module, in order to amend geometric defects due to manufacturing tolerances

Patent metadata

Field	Value
Publication number	US-11025873-B2
Application number	US-201816158531-A
Country	US
Kind code	B2
Filing date	Oct 12, 2018
Priority date	Oct 13, 2017
Publication date	Jun 1, 2021
Grant date	Jun 1, 2021

Abstract

A luminous motor-vehicle system including an optical module and aims to compensate for undesirable movement or deformation effects caused by the manufacturing tolerances of the optical portion. The module includes an imaging device provided with a pixelated spatial modulator, which is illuminated by a source, and a projecting optic. A control unit for controlling the modulator receives first display commands that are representative of an image to be projected. This unit converts each first display command into a second display command taking into account correction parameters, which are predefined on the basis of an identification of geometric defects specific to the projecting optic. The control unit controls the modulator, which may be a digital micromirror device, depending on the second display commands in order that the image actually projected by the imaging device corresponds to the image to be projected.

First claim

The invention claimed is:

1. A method for amending geometric defects in a light beam projected by an optical module of a motor vehicle, the optical module including an imaging device, provided with a high-definition pixelated spatial modulator and a projecting optic, and a light source for generating light intended for the modulator, the method comprising:
receiving a first display command to display an image to be projected, intended for the modulator, the first display command including image data of the image to be projected; and
converting the first display command into a second display command that takes into account correction parameters,
wherein the correction parameters are predefined on the basis of an identification of geometric defects that are specific to the projecting optic, by virtue of which the modulator is controlled so that the image actually projected using the imaging device corresponds better to the image to be projected than without said correction parameters taken into account, and
wherein the second display command differs from the first display command in selective activation of all or some of a row of pixels, said row being defined in a marginal zone by the modulator.

2. The method according to claim 1 , wherein the correction parameters are suitable for modifying activation statuses of the pixels defined by the modulator, in order to compensate for at least one among the following defects:
a lateral shift of an outline of the light beam transmitted by the projecting optic; and
a deformation of the outline of the light beam transmitted by the projecting optic.

3. The method according to claim 2 , wherein the correction parameters are suitable for modifying durations or frequencies of activation of the pixels of the modulator in order to compensate for a loss of clearness in the projected image close to a periphery of the light beam transmitted by the projecting optic.

4. The method according to claim 1 , wherein the correction parameters are suitable for modifying durations or frequencies of activation of the pixels of the modulator in order to compensate for a loss of clearness in the projected image close to a periphery of the light beam transmitted by the projecting optic.

5. The method according to claim 1 , wherein the correction parameters and/or the second display command are stored in a memory accessible to a control unit, the control unit being suitable for activating the second display command.

6. A method according to claim 1 , wherein the correction parameters are suitable for modifying activation statuses of the pixels defined by the modulator, in order to compensate for at least one among the following defects:
a lateral shift of the outline of the light beam transmitted by the projecting optic; and
a deformation of the outline of the light beam transmitted by the projecting optic.

7. The method according to claim 1 , wherein the correction parameters are suitable for modifying the durations or frequencies of activation of the pixels of the modulator in order to compensate for a loss of clearness in the projected image close to the periphery of the light beam transmitted by the projecting optic.

8. The method according to claim 1 , wherein the correction parameters and/or the second display command are stored in a memory accessible to a control unit, the control unit being suitable for activating the second display command.

9. A luminous system for a motor vehicle, allowing the method according to claim 1 to be implemented, the system including:
an optical module comprising:
an imaging device, provided with a high-definition pixelated spatial modulator and a projecting optic, and
a light source for generating light intended for the modulator, and
a control unit designed and arranged to control the modulator and suitable for receiving first display commands, each of the first display commands being representative of an image to be projected,
the control unit comprising adjusting means for converting each first display command into a second display command that takes into account correction parameters,
the correction parameters being predefined on the basis of an identification of geometric defects that are specific to each projecting optic, the control unit controlling the modulator depending on second display commands in order that the image actually projected by the imaging device corresponds better to the image to be projected than without the correction parameters taken into account.

10. A luminous system for a motor vehicle, allowing a method to be implemented for amending geometric defects in a light beam projected by an optical module of a motor vehicle, the optical module including an imaging device, provided with a high-definition pixelated spatial modulator and a projecting optic, and a light source for generating light intended for the modulator, the method including: receiving a first display command to display an image to be projected, intended for the modulator, the first display command including image data of the image to be projected; and converting the first display command into a second display command that takes into account correction parameters, the converting of the first display command into the second display command includes adjusting pixels of the image to be projected, wherein the correction parameters are predefined on the basis of an identification of geometric defects that are specific to the projecting optic, by virtue of which the modulator is controlled so that the image actually projected using the imaging device corresponds better to the image to be projected than without said correction parameters taken into account, the system including:
an optical module comprising:
an imaging device, provided with a high-definition pixelated spatial modulator and a projecting optic, and
a light source for generating light intended for the modulator, and
a control unit designed and arranged to control the modulator and suitable for receiving first display commands, each of the first display commands being representative of an image to be projected,
the control unit comprising adjusting means for converting each first display command into a second display command that takes into account correction parameters,
the correction parameters being predefined on the basis of an identification of geometric defects that are specific to each projecting optic, the control unit controlling the modulator depending on second display commands in order that the image actually projected by the imaging device corresponds better to the image to be projected than without the correction parameters taken into account.

11. The system according to claim 10 , wherein the high-definition pixelated spatial modulator comprises a digital micromirror device, micromirrors of the digital micromirror device each being movable between:
a first position in which the micromirror is arranged to reflect light rays that come thereto from the light source or from a light-ray emitting unit that includes said light source, in the direction of the projecting optic,
and a second position in which the micromirror is arranged to reflect the light rays that come thereto from the light source or from a light-ray emitting unit that includes said light source, away from the projecting optic.

12. The system according to claim 11 , wherein the control unit has access to a memory storing the correction parameters and/or information representative of the second display commands.

13. The system according to claim 12 , wherein the imaging device is suitable for projecting a segmented output light beam containing at least one cut-off.

Assignees

• Valeo Vision

Inventors

• Albou Pierre
• Godbillon Vincent

Classifications

• F21S41/63 Primary

  by acting on refractors, filters or transparent cover plates · CPC title

• F21S41/14

  characterised by the type of light source · CPC title

• F21W2102/00

  Exterior vehicle lighting devices for illuminating purposes · CPC title

• G01C21/365

  Guidance using head up displays or projectors, e.g. virtual vehicles or arrows projected on the windscreen or on the road itself · CPC title

• F21S41/147

  the main emission direction of the LED being angled to the optical axis of the illuminating device · CPC title