SYSTEM FOR PROJECTING A PATTERN OF INTEREST ONTO A RETINAL AREA OF A HUMAN EYE

Abstract

The present invention pertains to a system for projecting a pattern of interest onto a retinal area of a human eye, containing a carrying frame for being worn by a patient, a camera for capturing an image, a projector device for projecting a pulsed light beam reflecting a pattern of interest into a human eye, and a processor device being in communication with the camera and the projector device, wherein the processor device is adapted for converting the image captured by the camera into the pattern of interest being basis for the pulsed light beam, wherein the projector device and the camera are attached to the carrying frame.

Claims

1. A system for projecting an optical pattern of interest onto a modified retinal area of a human eye, containing a carrying frame for being worn by a patient, a camera for capturing an image, a projector device for projecting a pulsed light beam reflecting a pattern of interest into a human eye, and a processor device being in communication with the camera and the projector device, wherein the processor device is adapted for converting images captured by the camera into patterns of interest being basis for the pulsed light beam, wherein the projector device and the camera are attached to the carrying frame.

2. The system according to claim 1, characterized in that the processor device provided separate to the carrying frame, wherein a connection cable is provided for communication of the processor device with the camera and the projector device.

3. The system according to claim 1, characterized by further comprising a light source, wherein the light source is arranged in the projector device, or the light source is arranged in the processor device, wherein preferably the light source contains a laser, a laser diode, and/or an LED, preferably an LED-Matrix, wherein preferably the light source is adapted to emit light having a wavelength in the infrared field, and/or coherent light or incoherent light.

4. The system according to claim 1, characterized in that the processor device comprises a processor unit being adapted to provide controlling of a pulse duration and/or a frequency and/or light intensity of the light beam and/or of the light source.

5. The system according to claim 3, further comprising a modulation micromirror array, preferably a digital micromirror device, for modulating and dividing a pulsed input light beam emitted by the light source into a modulated light pattern of modulated pulsed sub-beams, wherein an orientation of each of the micromirrors of the micromirror array is individually controllable or controlled by sub-groups based on a pattern of interest, such that the sub-beams form a pulsed output beam reflecting the pattern of interest, wherein preferably the input light beam is directed towards the modulation micromirror array by an optical prism, preferably a total internal reflection prism.

6. The system according to claim 5, wherein the modulation micromirror array is arranged in the projector device or wherein the modulation micromirror array is arranged in the processor device.

7. The system according to claim 2, wherein the connection cable adapted to convey data between the processor device and the projector device and/or to convey camera data, and/or the connection cable adapted for providing electric power from the processor device to the camera and/or the projector device, and/or the connection cable is adapted to convey light from the processor device to the projector device, wherein preferably the connection cable comprises an electrical cable and/or an optical fiber or an optical cable.

8. The system according to claim 3, wherein the light source is arranged in the processor device, wherein the connection cable comprises the electrical cable and the optical fiber or optical cable, wherein the optical fiber optical cable provides connection of the light source with the projector device.

9. The system according to claim 8, characterized in that the connection cable and/or the projector device comprise a light safety interlock loop, preferably a laser safety interlock loop.

10. The system according to claim 1, characterized in that the projector device optics for projecting the light beam from the exterior of a human eye at a pupil of the eye, wherein preferably the optics are configured such that an exit pupil diameter of the light beam is set smaller than an eye pupil diameter of the eye.

11. The system according to claim 1, wherein the projector device comprises an alignment device for adjusting a position and/or orientation of the projector device with respect to the carrying frame, wherein preferably the alignment device is formed such that the projector device can be moved relative to the carrying frame in a plurality of movement directions, particularly preferably in five movement directions.

12. The system according to claim 11, wherein the carrying frame contains a spectacles frame, and/or wherein the frame contains a headband, and/or wherein the frame contains a headring and/or a flexible band.

13. The system according to claim 11, further comprising an eye tracking mechanism that monitors the eye position and/or angle, wherein the alignment device is configured for automatically aligning the projector device with an central eye axis, wherein preferably, the alignment device is motorized and/or the alignment device comprises tilting mirrors and/or piezoelectric motors, and/or a coupling feedback mechanism that automatically aligns the projector device with the central eye axis.

14. The system according to claim 1, wherein the carrying frame comprises a lens, wherein preferably the lens shaded, preferably tinted.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0061] The present disclosure will be more readily appreciated by reference to the following detailed description when being considered in connection with the accompanying drawings in which:

[0062] FIG. 1 is a schematic perspective side view of a system for projecting an optical pattern of interest onto a human eye according to a first embodiment;

[0063] FIG. 2 shows a schematic operation principle for projecting an optical pattern of interest on a photosensitive retinal implant of a human eye;

[0064] FIG. 3 schematically shows a system for projecting an optical pattern of interest onto a retina of a human eye according to another preferred embodiment; and

[0065] FIG. 4 schematically shows a perspective side view of a detail of a carrying frame according to another preferred embodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0066] In the following, the invention will be explained in more detail with reference to the accompanying figures. In the figures, like elements are denoted by identical reference numerals and repeated description thereof may be omitted in order to avoid redundancies.

[0067] FIG. 1 is a schematic perspective side view of a system 80 for projecting an optical pattern of interest onto a retina of a human eye according to a preferred embodiment. The system 80 comprises a carrying frame 50 which substantially comprises the form of a spectacles frame and which can be worn by a patient having a photosensitive retinal implant implanted into his eye or having a genetically modified retinal area. The system 80 further contains a projector device 1 which is adapted for projecting a pulsed output light beam which reflects the optical pattern of interest into the human eye, and a camera 6 for capturing an image. According to this preferred embodiment, the camera 6 is integrated and/or is aligned with the projector device 1. It must be noticed that in the followings the term “projector device” can designate the combination of the projector device with the camera present in the system. The projector device 1 is attached to the carrying frame 50 via a fastening section 5.

[0068] The projector device 1 is in communication with a processor device 60 by means of a connection cable 70. The processor device 60 is arranged separate to the carrying frame 50 and the projector device 1.

[0069] According to this embodiment, the projector device 1 comprises an integrated light source (not shown in this figure) which emits coherent laser light in the near infrared field, in this exemplary embodiment in a wavelength of 880 nm. Alternatively, the light may comprise any other wavelength suitable for interaction with a respective photosensitive retinal implant or genetically modified retinal cells.

[0070] According to another preferred embodiment, the light source is provided in form of an LED emitting incoherent light, preferably in the near infrared field.

[0071] The projector device 1 furthermore comprises a modulation micromirror array 3 (see FIG. 2), according to this preferred embodiment provided in form of a digital micromirror device. The modulation micromirror array 3 is adapted for modulating and dividing a pulsed input light beam emitted by the light source into a modulated light pattern consisting of modulated pulsed sub-beams, as will be explained in more detail with respect to FIG. 2.

[0072] The processor device 60 is in communication with the camera 6 and the projector device 1 via a cable 70. The processor device 60 furthermore is adapted for converting an image captured by the camera 6 into the pattern of interest which serves as the basis for the pulsed output light beam emitted by the projector device 1 (also named optical pattern in the specification)

[0073] Hence, via the light source, the collimated high-power input light beam is generated, directed through a TIR prism, such that it hits the active area of the modulation micromirror array 3 (FIG. 2). The active area here is constituted by those of the micromirrors of the micromirror array 3 which are oriented such that the modulated sub-beams forming the pattern are redirected through the TIR prism again and through a final lens, such that they leave the projector device 1 in form of the output beam towards and into the eye.

[0074] With other words, the processor device 60 uses the image taken by the camera 6 to form an optical pattern of interest. The processor device 60 allocates the micromirrors of the micromirror array 3 to one or more pixels of the pattern of interest and controls the orientation of each micromirror, such that the reflected sub-beams constituting the output beam reflect the optical pattern of interest.

[0075] FIG. 2 shows a schematic operation principle for projecting the optical pattern of interest 44 on the photosensitive retinal implant 90 of a human eye as described above. The light source 22 provides the pulsed input light beam 20 which is directed onto the modulation micromirror array 3 comprising the plurality of micromirrors 30 which can individually be controlled by the processor device 60 such that an orientation of each of the micromirrors 30 can individually be adjusted. Alternatively, the micromirrors 30 may be controlled and/or adjusted in sub-groups.

[0076] As described above, by means of the micromirror array 3, the input light beam 20 is modulated, thereby forming a first light signal or output beam 4 corresponding to the optical pattern. The orientation of the micromirrors 30 is individually adjusted by means of control commands from the processor device 60, such that the optical pattern of interest 44 which is to be projected onto the retinal implant 90 can be reflected by the plurality of sub-beams 40.

[0077] In this regard, the optical pattern of interest 44 is based on the content or image captured by the camera 6 which has been processed into a digital pattern of pixels by the processor device 60.

[0078] Hence, the first light signal or output beam 4 substantially reflects the optical pattern of interest 44. When the output beam 4 hits the retinal implant 90, only those parts of the retinal implant 90 are illuminated by means of the output beam 4 or in particular the sub-beams 40, which reflect the optical pattern of interest 44 at the retinal implant 90. Consequently, only those photosensitive diodes of the retinal implant 90 convert light into electric current, which are arranged in the projected optical pattern of interest 44. A person comprising the retinal implant 90, thus, can perceive the optical pattern of interest 44.

[0079] The carrying frame 50 comprises optional ear pads 52 which are displaceable along the temples 53 of the frame 50 such that the carrying frame 50 can be adjusted to a person's head size and/or other morphology characteristics, such as ear position and shape. The optional ear pads 52 can be configured to prevent the frame 50 to move with respect to the ear of a person wearing the frame 50. Hence, the earpads 52 may function as earstops.

[0080] The projector device 1 is arranged at the left side of the carrying frame 50, such that light is projected into the left eye of the patient wearing the carrying frame 50. A counterweight 51 is arranged on the side of the frame 50 opposite to the side at which the projector device 1 is arranged such that the lateral weight distribution of the carrying frame 50 is balanced.

[0081] Alternatively or in addition, a projector device 1 may be arranged at the right side of the carrying frame 50, such that light is projected into the right eye of the patient wearing the carrying frame 50. Preferably, the projector devices 1 are the same for both left and right configurations, wherein preferably, a first projector device 1 is mounted with 180° rotation difference with regard to a second projector device 1.

[0082] FIG. 3 shows a system 80 for projecting an optical pattern of interest onto a retina of a human eye according to another preferred embodiment. The system 80 substantially corresponds to the system shown in FIG. 1, wherein in this embodiment, the light source is arranged in the processor device 60. The connection cable 70, thus, comprises an electrical cable 71 for providing electric power and control commands to the projector device 1 and to the camera 6 and also a camera stream from the camera 6 to the processor device 60, and an optical fiber 72 to convey light emitted by the light source from the processor device 60 to the projector device 1. With other words, the connection cable 70 is a hybrid cable providing both electrical and optical conduction. With other words, both electrical and optical information is conducted via connection cable 70.

[0083] Furthermore, the connection cable 70 comprises a laser safety interlock loop (not shown). By means of the laser safety interlock loop, a damage to the connection cable 70 can be detected. In case the laser safety interlock loop is open due to a damage, for instance, of the optical fiber 72, a switch (not shown) arranged in the processor device 60 interrupts connection between the light source arranged in the processor device 60 and the connection cable 70.

[0084] FIG. 4 schematically shows a perspective side view of a detail of a carrying frame 50 according to another preferred embodiment. The projector device 1 comprises an alignment device 8 by means of which the position and the orientation of output light beam 4 can be adjusted with respect to the carrying frame 50, thus with respect to the human eye of the patient wearing the carrying frame 50.

[0085] The alignment device 8 is formed such that optics 2 through which the light beam 4 exits the projector device 1 can be moved relative to the fastening section 5 in five movement directions 10, 11.

[0086] Three movement directions are longitudinal directions 10, 10′, 10″, wherein optionally each longitudinal direction is oriented substantially orthogonal to the other longitudinal directions. In this exemplary embodiment, a first longitudinal movement direction 10 corresponds to a longitudinal axis of a human head, a second longitudinal movement direction 10″ corresponds to a transversal axis of a human head, and a third movement longitudinal direction 10′ corresponds to a sagittal axis of a human head. The two remaining movement directions are directions of rotation 11, 11′. In this exemplary embodiment, a first direction of rotation 11′ is oriented such that a pantoscopic angle of the optics 2 with respect to the eye can be adjusted, and a second direction of rotation 11 is oriented such that a wrap angle of the optics 2 with respect to the eye can be adjusted.

[0087] For providing the movement directions 10, 10′, 10″, 11, and 11′, the alignment device 8 comprises a plurality of kinematic pairs which are shown in generic form, as kinematic pairs are per se known. The longitudinal movement directions 10, 10′, 10″ are provided by means of prismatic joints. In detail, one of the prismatic joints is arranged in proximity to the fastening section 5. This prismatic joint provides linear movement in the longitudinal movement direction 10. A second prismatic joint is arranged adjacent to the first prismatic joint and provides movement along the longitudinal movement direction 10′. Adjacent thereto, a first rotating joint is arranged, which provides rotation in the direction of rotation 11. Moreover, a further prismatic joint is provided for enabling movement in longitudinal movement direction 10″. In addition, a further rotational joint is provided for providing rotation in direction of rotation 11′.

[0088] Furthermore, alignment device 8 comprises a plurality of locking units, wherein each of the locking units (not shown) is allocated to a respective kinematic pair for locking or releasing movement in the respective movement direction. Locking units are per se known, and for instance may be implemented in the form of a locking screw or a surface comprising a high coefficient of friction.

[0089] Preferably, the carrying frame comprises a rigid design to ensure robust positioning. Alternatively, the carrying frame comprises at least a robust part to ensure robust and repeatable placement in front of the eye, while some other part of the frames, e.g. the temples, may be provided be more flexible to accommodate different patient's head sizes or other morphology adjustments while keeping a robust positioning.

[0090] As can be seen in FIG. 4, the main axis Z.sub.1 of the camera 6 is aligned with a main axis Z.sub.2 of the optics 2 and hence with the center 42 of the output light beam 4. According to this exemplary embodiment, the main axis Z.sub.2 and the main axis Z.sub.1 are concentrically aligned. With other words, the camera 6 and the optics 2 are arranged in line facing opposite sides of the projector device 1.

[0091] The frame 50 furthermore comprises optional lenses 54 which according to this embodiment are shaded, here tinted. By providing the tinted lens 54, the eye pupil diameter is naturally enlarged as less ambient light falls into the eye pupil such that alignment by the alignment device is facilitated.

LIST OF REFERENCE NUMERALS

[0092] 1 projector device [0093] 2 optics [0094] Z.sub.2 main axis of the optics [0095] 5 fastening section [0096] 6 camera [0097] Z.sub.1 main axis of camera [0098] 8 alignment device [0099] 10 longitudinal movement direction [0100] 11 direction of rotation [0101] 20 input light beam [0102] 22 light source [0103] 3 micromirror array [0104] 30 micromirror [0105] 4 output beam [0106] 40 sub-beam [0107] 42 center of the light beam [0108] 44 pattern of interest [0109] 50 frame [0110] 51 counter weight [0111] 52 earpad [0112] 53 temple [0113] 54 lens [0114] 60 processor device [0115] 70 connection cable [0116] 71 electric cable [0117] 72 optical fiber [0118] 80 system [0119] 90 retinal implant