US 12,332,470 B2
Device for projecting an image into the eye of a user
Fabian Rainouard, Grenoble (FR); and Christophe Martinez, Grenoble (FR)
Assigned to Commissariat A L'Energie Atomique et aux Energies Alternatives, Paris (FR)
Filed by Commissariat A L'Energie Atomique et aux Energies Alternatives, Paris (FR)
Filed on May 11, 2022, as Appl. No. 17/741,784.
Claims priority of application No. 21 05017 (FR), filed on May 12, 2021.
Prior Publication US 2022/0381968 A1, Dec. 1, 2022
Int. Cl. G02B 6/00 (2006.01); F21V 8/00 (2006.01); G02B 27/01 (2006.01); G02F 1/29 (2006.01)
CPC G02B 6/005 (2013.01) [G02B 27/0172 (2013.01); G02F 1/292 (2013.01); G02B 2027/0178 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A device for projecting an image onto an eye, the device comprising a stack comprising:
light guides, each light guide being coupled to a plurality of diffraction gratings, which are distributed over a length of the light guide, each diffraction grating being electrically modulatable, each diffraction grating being configured to be electrically modulated so as to extract light propagating through the light guide;
electrodes, each electrode being associated with a plurality of diffraction gratings coupled to various light guides, respectively, each electrode being configured to modulate each diffraction grating with which it is associated; and
the device comprising various emission points distributed over the length of an emission area, each emission point corresponding to an association between one electrode and one diffraction grating coupled to one light guide,
wherein:
each light guide extends in such a way as to form rectilinear segments, two successive rectilinear segments of a given light guide making two different acute angles (α, −α) to a longitudinal axis, respectively;
rectilinear segments of various light guides are placed parallel to one another, but offset from one another in a direction perpendicular to the longitudinal axis;
the emission points are distributed in such a way as to form subsets, the emission points of a given subset being formed by a group of electrodes superposed on a group of light guides, such that each electrode of the group of electrodes is configured to modulate the diffraction gratings coupled to various light guides of the group of light guides; and
the emission points of a given subset are configured to emit a light wave in the same direction.