Visual instrument for projecting optical signals

Abstract

The present invention provides a projection system (22) adapted to project an optical signal onto a first region (23) of the retina of the eye (19) of a wearer (12) of the visual instrument (10); an optical signal generator (20) for generating the signal to be projected; a waveguide (24) comprising an input coupler (24B) and an output coupler (24C), the waveguide (24) adapted to transmit light from the input coupler (24B) to the output coupler (24C); and optionally a second optical line (18) comprising an optical system (44) adapted to project an environmental light signal onto a second region (46) of the retina of the eye (19) of the wearer (12).

Description

[Technical field]

[0001] The present invention relates to a visual instrument and method for projecting an optical signal. [Background technology]

[0002] The present solution aims to stimulate retinal ganglion cells for optogenetic therapy.

[0003] The retina is composed of photoreceptors, highly specialized neurons that are responsible for retinal light sensitivity through phototransduction, i.e., the conversion of light into electrical and chemical signals that carry the sequence of events in the visual system, ultimately resulting in the representation of the universe. In the vertebrate retina, phototransduction is initiated by the light-sensitive receptor protein, rhodopsin.

[0004] Loss or degeneration of photoreceptors, such as retinitis pigmentosa (RP) or macular degeneration (MD), severely impairs, if not completely prevents, the phototransduction of visual information in the retina. Loss of photoreceptor cells and / or loss of photoreceptor cell function is the leading cause of reduced vision, reduced light sensitivity and blindness.

[0005] Several treatments are currently being developed for retinal degenerative diseases, including gene therapy, stem cell therapy, optogenetics and retinal prostheses.

[0006] For example, a genetic and neuroengineering technique called optogenetics has been proposed to restore light sensitivity to a targeted retina by controlling the activity of a defined group of neurons without affecting other neurons in the brain. In contrast to conventional gene therapy, which attempts to replace or repair defective genes by correcting defective or dysfunctional proteins or to bypass genetic defects, optogenetic approaches can endow normally non-light-sensitive cells in the retina with the ability to respond to light, thus restoring useful vision to patients. Unlike retinal chip implants, which provide extracellular electrical stimulation to bipolar or ganglion cells, optogenetics-based therapy stimulates cells from within the cells.

[0007] Optogenetics refers to the combination of genetics and optics to control well-defined events in specific cells of living tissues. Optogenetics involves (i) genetically modifying targeted cells to render them sensitive to light by expression of an exogenous photoreactive protein in the cell membrane, and (ii) providing an illumination device capable of providing light to the photoreactive protein.

[0008] Examples of exogenous photoreactive proteins are provided in WO 2007 / 024391, WO 2008 / 022772 or WO 2009 / 127705, which describe the use of opsin genes from plants and microbial organisms (e.g., archaea, bacteria and fungi) to encode light-activated ion channels and pumps (e.g., channelrhodopsin-2 [ChR2]; halorhodopsin [NpHR]) designed for expression in mammalian neurons and can be genetically targeted to specific neural populations using viral vectors. When exposed to light with the appropriate wavelength, they can trigger action potentials, thereby rendering those cells light-sensitive. Similarly, WO 2013 / 071231 discloses novel channelrhodopsins, Chronos and Chrimson, which have different activity spectra from each other and from the prior art (e.g. ChR2 / VChR1), and use various and distinct wavelengths of light to depolarize different sets of cells in the same tissue by expressing channels with different activity spectra genetically expressed in different cells, and then illuminating the tissue with different colors of light. Photoreactive proteins, as disclosed in WO 2017 / 187272, are another alternative.

[0009] Optogenetics is a very powerful tool for selective neuronal activation / inhibition and can be used to restore neuronal function, particularly in the eye, in living animals, including, for example, humans.

[0010] However, it has been shown that the wavelength of light selected must be close to the optimal wavelength of the photoreactive protein, and that these photoreactive proteins have very low sensitivity to light. Thus, to obtain a maximum level of protein activation by light, the intensity of light received by the target cell or protein must be above a certain minimum value, and as a result, an external device providing sufficient radiation at a suitable wavelength is required.

[0011] Alternatively, it has been proposed to at least partially restore the vision of these patients using visual prosthesis systems. These systems contain retinal implants and are useful tools for at least partially restoring some visual perception and sense of orientation for blind and visually impaired users by taking advantage of the fact that, although some of the retinal tissue is degenerated, most of the retina is intact and can be directly stimulated by light-dependent electrical stimulation. Typically, retinal implants are implanted in the patient's eye and provide electrical excitation of the remaining neuronal cells in response to light stimulation. When stimulated, these remaining neuronal cells send artificially induced electrical impulses through the optic nerve to the visual cortex of the brain.

[0012] Retinal implants can be broadly classified into two categories: epiretinal and subretinal. Epiretinal devices are placed on or near the inner surface of the retina, i.e., the side of the retina that is first exposed to the incoming light and where the nerve fibers of the ganglion cells pass on their path towards the optic nerve. Typically, epiretinal implants comprise a chip with multiple pixel elements that can receive an image projected through the lens of the eye onto the retina by an extraocular device (typically a camera and micro-electrical circuitry to decode the incoming light), convert the image into an electrical signal, and further convert the signal into an electrical impulse via multiple stimulation electrodes to stimulate the retinal cells adjacent to the chip, reconstructing or improving the vision of blind or partially blind patients. In contrast, subretinal devices are placed underneath the retina, between the retina and the underlying retinal pigment epithelium or other deeper tissues. Currently available subretinal technologies rely on a single, rigid, and typically planar chip. It has further been shown that it would be desirable to be able to implant two or more chips to cover a wide field of view.

[0013] Retinal prostheses and optogenetic therapy depend on two main components. The first component, engineered on the retina, provides light sensitivity by providing a change in the membrane potential of the target retinal cells; that is, it is an implant in a retinal prosthesis system, or in optogenetic therapy, a light-gated ion channel protein genetically introduced into the retinal cells. The second component is required to encode the visual information (usually acquired by a camera or an array of photodiodes) and convert it into the input signal required by the previous component. In retinal prostheses, the input signal is a current delivered by a platform of active electrodes or by a pulse that can activate a passive component. In optogenetic gene therapy, the input signal delivered is a pulse of light of the appropriate intensity and wavelength required to activate the optogenetic protein in a defined spatial-temporal manner.

[0014] The required light emission cannot be achieved with standard headsets.

[0015] In particular, known solutions comprise a projector for projecting an image onto the retina, which does not allow a field of view wider than 10°, which is not sufficient in some cases.

[0016] Furthermore, the heat generated by the required powerful light source and the control electronics induces a temperature increase that must be kept within the limits set by the standard ISO 60601-1 for medical electrical equipment. The device must also ensure electrical safety (ISO 60601-1) and electromagnetic compatibility (ISO 60601-1-2, ISO 60601-1).

[0017] Furthermore, the increased temperature and increased heat transfer of the device in front of the eye can lead to dry eye and discomfort. Therefore, additional temperature restrictions are needed for the portion of the device near the eye.

[0018] It is desirable to provide a visual device that is capable of conveying a wider field of view with sufficient light intensity, whilst maintaining a sufficient level of comfort, particularly in terms of temperature, for the wearer.

[0019] More specifically, it is desirable to provide an optical instrument that can confine excess thermal energy from the light source and control electronics and / or facilitate heat dissipation so as to prevent the temperature of the lighting device from exceeding its maximum temperature for normal operation and to provide an extended field of view.

[0020] Furthermore, it is desirable to provide a lighting device that is miniaturized so that it can be worn by humans on a daily basis. Summary of the Invention [Problem to be solved by the invention]

[0021] Thus, there is a need for a visual instrument adapted to project an optical signal into the eye of a wearer of the instrument, capable of obtaining an extended field of view, being more compact, and providing improved comfort and perception for the wearer. [Means for solving the problem]

[0022] To this end, the present specification provides a visual instrument comprising: (i) a projection system adapted to project a first optical signal onto a first region of a retina of an eye of a wearer of the visual instrument; (ii) an optical signal generator that generates the first optical signal to be projected; and (iii) a first optical line comprising an input coupler and an exit coupler, the waveguide being adapted to transmit light from the input coupler to the exit coupler.

[0023] According to a preferred embodiment, the visual instrument further comprises a second optical line comprising an optical system adapted to project a second light signal of the environment (i.e., the environmental light signal) towards a second region of the retina of the wearer's eye.

[0024] According to further aspects of the invention, which are advantageous but not required, the visual apparatus may incorporate one or more of the following features, in any technically permissible combination: The optical signal generator comprises a total internal reflection prism (TIR prism) adapted to direct the beam of incoming light at an angle, said angle being preferably comprised between 20° and 40°. The optical signal generator includes a total internal reflection prism (TIR prism) along with a digital micromirror device (DMD) imager. The first optical line and the second optical line are positioned such that there is no intersection between the first region and the second region. The first optical line and the second optical line are positioned such that the second region surrounds the first region. A primary direction of light propagation is defined for the waveguide, and the second optical line and the waveguide are arranged such that light in the second optical line propagates along a general direction that is perpendicular to the primary direction of light propagation in the waveguide. The waveguide is fabricated from a semi-transparent material, preferably a transparent material. The first optical line is a bent line. The second optical line is the unfolded line. The optical signal generator comprises a light source. The optical signal generator comprises a light source, and the first optical line comprises a collimating lens, a total internal reflection prism (TIR prism), a digital micromirror device (DMD) imager, and a projection lens. The optical signal generator comprises a light source, the light source being a fiber light source. The optical signal generator comprises a light source, the light source being an electroluminescent diode, more preferably a light emitting diode (LED) or an LED derivative (eg an OLED). The source of the second light signal is the wearer's environment. The visual instrument is part of, constitutes or is associated with the goggles. The visual instrument is a virtual reality instrument. A second optical line is parallel to the line of sight of the wearer's eye. The field of view of the projection system extends from 15° to 25° along a first direction and from 25° to 35° along a second direction perpendicular to the first direction.

[0025] The present specification also relates to a method for projecting an optical signal to an eye of a wearer of a visual instrument, comprising: (ii) a projection system adapted to project a first optical signal to a first area of ​​a retina of the eye of the wearer of the instrument; (iii) a first optical line comprising an optical signal generator for generating the first optical signal to be projected; and (iv) a waveguide comprising an input coupler and an output coupler, adapted to transmit light from the input coupler to the output coupler. According to a preferred embodiment, the visual instrument used in the method of the present invention further comprises a second optical line comprising an optical system adapted to project a second optical signal of the environment to a second area of ​​the retina of the wearer's eye.

[0026] According to a particularly preferred embodiment, the method includes the steps of simultaneously projecting a first light signal by a first optical line and projecting a light signal of the environment by a second optical line.

[0027] The invention will be better understood on the basis of the following description, given by way of illustrative example in conjunction with the accompanying drawings, which are not intended to limit the subject matter of the invention. [Brief description of the drawings]

[0028] [Figure 1] 1 illustrates diagrammatically an example of a visual instrument in the context of use by a wearer; [Diagram 2] FIG. 2 is a detailed view of a portion of the visual apparatus of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] A visual instrument 10, a wearer 12 and a portion of the wearer's environment 14 are shown in Figure 1. The portion of the environment includes a tree 14A.

[0030] Vision instrument 10 is an instrument used by a wearer 12 of instrument 10 to view a portion 14 of the environment.

[0031] An example of an illustrative visual instrument 10 is shown in more detail in FIG.

[0032] A first direction is defined parallel to axis X and is referred to as the "first direction X". A second direction is defined parallel to axis Y and perpendicular to axis X and is referred to as the "second direction Y". A third direction is defined parallel to axis Z and perpendicular to axes X and Y and is referred to as the "third direction Z".

[0033] The visual instrument 10 includes two optical lines, a first optical line 16 and a second optical line 18 .

[0034] The optical line is the set of elements along the optical line that connects the source of the optical signal to the eye 19 of the wearer 12 .

[0035] According to a preferred embodiment of the invention, the optical signal is an image.

[0036] The first optical line 16 is a curved line.

[0037] By "broken line" it is understood that the elements are arranged such that the beam of light along the first optical path has multiple angled connections 16A.

[0038] The first optical line 16 includes an optical signal generator 20 , a projection system 22 and a waveguide 24 .

[0039] The optical signal generator 20 is adapted to generate a first optical signal to be projected.

[0040] The optical signal generator 20 includes a light source 26 , a collimating lens 28 , a total internal reflection (TIR) ​​prism 30 , and a digital micromirror device (DMD) 32 .

[0041] In some cases the term DMD imager is seen for element 32 .

[0042] According to the example of FIG. 2, the path of the first optical line 16 follows the path of elements 26 , 28 , 30 , 32 , 30 .

[0043] The light source 26 includes a light emitting element 34 adapted to generate light.

[0044] The light generated is selected depending on the use of the visual device of the present invention. For example, in the case of use of the visual device by a person wearing a retinal implant with a photodiode, the light-emitting element is adapted to generate a light intensity that stimulates the photodiode of the implant. Similarly, in the case of use of the visual device by a person who has benefited from an optogenetic treatment, the light-emitting element is adapted to provide a light intensity at a wavelength specific to this application, stimulating the treated area.

[0045] Thus, the light emitting element 34 is selected with a spectral range and / or intensity that depends in particular on the expected application. For example, the light emitting element 34 may be a laser source or an incoherent light source.

[0046] In a preferred embodiment, light emitting element 34 is an incoherent light source.

[0047] For example, light emitting elements 34 include electroluminescent diodes, and more specifically, light emitting diodes (LEDs) or LED derivatives (eg, OLEDs).

[0048] In a specific example, the light source 26 further comprises an optical fiber 36 that conveys light to the light emitting element 34 .

[0049] More precisely, and by way of specific example, the light source 26 is an electroluminescent diode (not shown) followed by an optical fiber 36 .

[0050] In other words, the light source 26 is a fiber LED.

[0051] In a preferred embodiment, the light emitting element 34 is adapted to provide light at a wavelength capable of depolarizing cells containing a light-activated ion channel polypeptide. Examples of wavelengths of light that can be used to depolarize cells expressing a light-activated ion channel polypeptide include wavelengths of at least about 365 nm, 385 nm, 405 nm, 425 nm, 445 nm, 465 nm, 485 nm, 505 nm, 525 nm, 545 nm, 565 nm, 585 nm, 590 nm, 605 nm, 625 nm, 645 nm, 665 nm, 685 nm, and 700 nm or more, including all wavelengths therebetween. In a preferred embodiment, the light emitting element 34 is adapted to provide a light intensity at a wavelength of 365 nm to 700 nm, preferably 530 nm to 640 nm, preferably 580 nm to 630 nm, preferably 530 nm to 610 nm, and more preferably the wavelength of light is about 595 nm.

[0052] As used herein, the term "about" when used in connection with a numerical quantity means plus or minus 10% of that numerical quantity.

[0053] The collimating lens 28 is adapted to collimate an incoming beam of light 31 coming from the light source 26 .

[0054] The beams of light 31 emerging from the collimating lens 28 are substantially parallel to one another along a first direction X.

[0055] For example, collimating lens 28 has a focal length selected from 2 millimeters (mm) to 20 mm, more specifically, from 3 mm to 18 mm, and even more specifically, collimating lens 28 has a focal length of approximately 5.9 mm.

[0056] Total internal reflection prisms are often referred to as TIR prisms by using the acronym Total Internal Reflection. TIR prisms are well known in the art.

[0057] The TIR prism 30 is adapted to steer an incident beam of light 31 at an angle α (hereinafter referred to as the "steering angle α").

[0058] The TIR prism 30 includes an input surface 30A, an output surface 30B, a reflecting surface 30C, and an input prism 30 1 and output prism 30 2 Equipped with.

[0059] The entrance face 30A receives an incident beam of light.

[0060] The beam of light exits the TIR prism 30 at output face 30B.

[0061] For example, input face 30A and output face 30B are perpendicular to each other.

[0062] The steering angle α is determined by the prism 30 1 and the normal to the digital micromirror device 32.

[0063] For example, the steering angle α is included in the range of 20° to 40°.

[0064] By definition, α included between values ​​A and B means that α is greater than or equal to value A, and that α is less than or equal to value B.

[0065] In a particular embodiment, the steering angle α is equal to 24°.

[0066] The entrance surface 30A is the input prism 30 1 , and the output surface 30B belongs to the output prism 30 2 Belongs to.

[0067] The reflecting surface 30C is the reflecting surface of the input prism 30 1 Belongs to.

[0068] Input Prism 30 1 and output prism 30 2have complementary faces.

[0069] A small gap 40 is formed in the input prism 30 1 and output prism 30 2 A small gap 40 is defined between their complementary surfaces.

[0070] The digital micromirror device 32 is often referred to as DMD, using the acronym Digital Micromirror Device.

[0071] DMDs are well known in the art. A DMD comprises an array of mirrors (e.g., a 608x684 array or a 912x1140 array) that can be periodically (e.g., every 0.35 milliseconds (ms)) switched between two separate angular positions called ON and OFF, where the ON position reflects incoming light towards a target. Processed events are encoded by setting the corresponding mirror ON.

[0072] The digital micromirror device 32 is connected to the input prism 30 1 and arranged in the optical path of the beam of light reflected by the reflective surface 30C of the output prism 30 to direct at least a portion of the beam of light to the output prism 30. 2 The light is adapted to be reflected toward the

[0073] The digital micromirror device 32 may or may not allow a certain number of pixels to form the projected light signal.

[0074] The digital micromirror device 32 comprises a plurality of mirrors forming an array of micromirrors.

[0075] Each mirror has at least two positions.

[0076] In the first position, the mirror is positioned so that the light passes through the output prism 30 2The beam of light is directed through output prism 30 to pass through output face 30B and out through output face 30B. 2 is reflected toward the

[0077] In the second position, the mirror reflects the beam of light such that the light is not output from output surface 30B.

[0078] The projection system 22 is adapted to project a first optical signal onto a first area 23 of the retina 19 A of the eye 19 of the wearer 12 of the visual instrument 10 .

[0079] In the example, the projection system 22 is a projection lens 42 .

[0080] The field of view of the projection system extends from 15° to 25° along a first direction and from 25° to 35° along a second direction perpendicular to the first direction.

[0081] Waveguide 24 includes a body 24A, an input coupler 24B, and an exit coupler 24C.

[0082] Waveguide 24 is adapted to convey light from input coupler 24B to output coupler 24C.

[0083] According to a preferred embodiment, all or a portion of the body 24A of the waveguide 24 is fabricated from a translucent material.

[0084] In the following description, the term "semi-transparent" refers to a light-transmitting body having a light transmittance of 5% to 100%.

[0085] More preferably, all or a portion of the body 24A is made from a transparent material.

[0086] The term "transparent" refers to a light-transmitting body having a light transmittance of more than 95%, for example close to 100%. In particular, such a "transparent" body transmits light by refraction, and objects can be clearly seen through the "transparent" body.

[0087] The light in the waveguide 24 is composed of electromagnetic waves with wavelengths between 500 nanometers (nm) and 700 nm.

[0088] Furthermore, the body 24A of the waveguide is a parallelepiped.

[0089] 2, a main direction is defined for the waveguide 24 that is defined by the length of the body 24 of the waveguide 24. Such main direction is the main direction for the transmission of light by the waveguide 24.

[0090] An inner surface 24D and an outer surface 24E are defined about the body. The inner surface 24D and the outer surface 24E are perpendicular to the second direction Y.

[0091] The inner surface 24D is intended to be oriented towards the vision instrument's projector system 22 and the wearer's eye 19 when the vision instrument is worn.

[0092] The exterior surface 24E is intended to be oriented towards a portion of the environment 14.

[0093] In the particular example of FIG. 2, the main direction is along a first direction X.

[0094] The input coupler 24B and the output coupler 24C are disposed on an inner surface 24D of the body 24A.

[0095] For example, the input coupler 24B is disposed at one end of the inner face 24D, and the output coupler 24C is disposed at the other end of the inner face 24D along the main direction.

[0096] The input coupler 24B faces the projection lens 42.

[0097] Input coupler 24 B forms the entrance region of waveguide 24 , through which the beam of light exiting projector system 22 enters.

[0098] The input coupler 24B includes a surface treatment on a portion of the inner surface 24D of the body 24A.

[0099] The input coupler 24B is fabricated from a thin film of polymer.

[0100] By definition, a thin film is a film that is less than 10 micrometers (μm) in thickness.

[0101] By definition, an object is made of a polymer if the material of the object has a polymer content of 80% or more.

[0102] According to a specific embodiment, the polymer is a silver halide.

[0103] The exit coupler 24C faces the eye 19 of the wearer 12.

[0104] The exit coupler 24C forms the output region of the waveguide 24.

[0105] The outlet coupler 24C includes a surface treatment on a portion of the interior surface 24D of the body 24A.

[0106] The outlet coupler 24C is formed from a thin film of polymer.

[0107] The second optical line 18 is an unbent line.

[0108] An unbent line is understood to mean that the elements of the second optical line 18 are aligned such that the beam of light along the second optical line 18 has a substantially straight path 18A relative to the path of the beam of light along the first optical line 16.

[0109] In particular, the second optical line 18 is parallel to the line of sight of the wearer's eye 19. For example, the second optical line is parallel to the second direction Y.

[0110] The second optical line 18 comprises an optical system 44 adapted to project / transmit a second optical signal of the environment to a second area 46 of the retina 19A of the wearer's eye.

[0111] In a specific embodiment, optical system 44 is part of waveguide 24, referred to as 25. It may also be separate from waveguide 24. Alternatively, second optical line 18 reaches directly from the environment to the wearer's eye.

[0112] The limits of this portion 25 of the waveguide are defined by the range of optical viewing angles of the wearer 12 .

[0113] More precisely, portion 25 is the common portion of the waveguide in the range of the viewing angle of the wearer 12 .

[0114] Section 25 includes output coupler 24C.

[0115] The second optical line 18 and the waveguide 24 are arranged such that light in the second optical line 18 propagates along a general direction that is perpendicular to the primary direction of the waveguide 24. For example, the general direction is along a second direction Y.

[0116] The two optical lines 16, 18 are positioned such that they have no intersection with the first region 23 and the second region 46 of the retina 19A. The space between the first region 23 and the second region 46 is referred to as the "void region 48."

[0117] Alternatively, or in combination with the previous arrangement, the two optical lines 16 , 18 are arranged such that the second region 46 surrounds the first region 23 .

[0118] According to a particular embodiment, the visual instrument 10 comprises at least one lens, for example an eyepiece, for correcting visual field defects. Preferably, such a lens for correcting visual field defects is located between the output coupler 24C and the wearer's eye and / or the optical line 18 in front of the wearer's eye.

[0119] According to specific embodiments, the visual instrument 10 includes at least one optical filter, e.g., a colored optical filter, which may be located along the optical line 16 (e.g., between the collimating lens 28 and the total internal reflection prism 30, and / or between the total internal reflection prism 30 and the digital micromirror device 32, and / or between the DMD and the projection lens 42, and / or between the projection lens and the waveguide 24) and / or along the optical line 18.

[0120] The operation of the visual instrument 10 will now be described with reference to a method for projecting an optical signal to the wearer's eye.

[0121] According to a specific embodiment, the visual instrument 10 is in the form of a pair of eyeglasses.

[0122] The method includes a providing step, a positioning step, and two projecting steps.

[0123] During the provision process, the visual instrument 10 is provided to the wearer 12 .

[0124] As a specific example, an eye professional provides the vision device 10 to a wearer 12 .

[0125] In the placement step, the wearer takes the visual device and places it on the wearer's head, in front of the wearer's eyes.

[0126] For example, when the visual instrument 10 includes a fastening band, the wearer 12 uses the fastening band to fasten the visual instrument 10 to the wearer's head.

[0127] The two projection steps are accomplished simultaneously.

[0128] The first projection step projects a first optical signal by the first optical line 16 onto a first area 23 of the retina 19A.

[0129] The first optical signal to be projected is generated by an optical signal generator 20 .

[0130] More precisely, an incoming light beam 31 generated by the fiber LED 26 is sent to a TIR prism 30 .

[0131] The beam of light 31 is reflected by the reflective surface 30 C of the input prism 30 towards the micromirror device 32 .

[0132] Depending on the position of the micromirrors of micromirror device 32, the beam of light is split into a selected portion that reproduces the projected light signal and a portion that is discarded.

[0133] The selected portion is the output prism 30 2 is projected through

[0134] The beam of light exiting output face 30B is directed to a projection lens 42.

[0135] The beam of light exiting the projection lens 42 is transmitted to the waveguide 24 through the input coupler 24B.

[0136] The body 24 A of the waveguide 24 conveys the beam of light to an output coupler 24 C, which causes the beam of light to exit the waveguide 24 .

[0137] The beam of light exiting the output coupler is projected onto a first area 23 of the wearer's 12 retina.

[0138] At the same time, the method includes a second projection step.

[0139] By the second projection step, the optical signal of the environment (ie, the second optical signal) is projected by the second optical line 18 .

[0140] A beam of light from the environment passes through the body 24A of the waveguide 24 and reaches a second region 46 of the retina 19A.

[0141] The beam of light from the waveguide is transmitted by external face 24E into body 24A, traverses body 24A, exits the waveguide by output coupler 24C, and is projected onto a second region 46 of retina 19A.

[0142] The waveguide 24 allows the optical signal generator 20 to be positioned away from the wearer's field of vision while still preserving the patient's peripheral vision without impairment.

[0143] The use of fiber LEDs 26 in conjunction with a reflecting prism 30 also allows the LEDs to be moved away from the projection system, thus reducing heating issues for the wearer 12.

[0144] Furthermore, a second optical signal projected by a second optical line 18 completes the optical signal projected by the first optical line in order to reconstruct a portion of the environment.

[0145] Additionally, the second optical line 18 ensures that the second signal is projected onto a second region 46 of the retina 19A that does not have an overlapping area with the first region 23 of the retina 19A.

[0146] Furthermore, the visual instrument 10 of the present invention makes it possible to obtain a device that is independent of the pupil size, especially when the pupil size is greater than 3 millimeters (mm) in diameter.

[0147] The visual instrument 10 also enables the required radiation to be delivered to the retina 19A of the wearer 12.

[0148] The visual instrument 10 is also compact. Elements of the first optical line 16 can be positioned closer to the waveguide 24, especially when the first optical line 16 is a bent line.

[0149] Therefore, the dimension of the visual device along the second direction is small compared to known visual devices.

[0150] Such an optical instrument also provides the wearer with a 20°×30° field of view, by virtue of the use of the instrument 10 in general, and the TIR prism 30 in particular, in conjunction with the digital micromirror device 32 .

[0151] The visual instrument 10 does not obscure the patient's field of vision.

[0152] According to a particular embodiment, the projection system 22 and / or the optical signal generator 20 are attached to the frames of a pair of eyeglasses.

[0153] The visual device 10 can be used in the field of vision restoration using visual prostheses, for example retinal implants.

[0154] According to a specific embodiment, the visual instrument 10 is an instrument adapted for optogenetics.

[0155] The above-defined device 10 may be used for a subject (e.g., a wearer) suffering from a loss or degeneration of photoreceptors, such as retinitis pigmentosa (RP) or macular degeneration (MD). As described above, these diseases result in reduced visual acuity, reduced light sensitivity, or blindness of part of the subject's visual field.

[0156] As explained above, some treatments involve stimulating the transfected retinal cells and / or retinal implants with a beam of light.

[0157] A first region 23 of the retina onto which an optical signal is intended to be projected by the first optical line 16 contains cells, more specifically, retinal cells that have been genetically modified to express a light-gated ion channel protein for optogenetic therapy.

[0158] According to specific embodiments, the light-gated ion channel protein is selected from the group consisting of Chrimson, ChrimsonR (WO 2013 / 71231, ChrimsonR-tdT (WO 2017 / 187272), Catch, Channelrhodopsin (US 2014 / 0121265, US 8,906,360) and melanopsin, and derivatives thereof.

[0159] A first area 23 of the retina onto which the optical signal is intended to be projected by the first optical line 16 comprises the retina that needs to be stimulated.

[0160] That area of ​​the retina is stimulated by a beam of light that reproduces the optical signals of the environment, or more specifically, an image.

[0161] The projected light signal reconstructs lost vision due to photoreceptor loss or degeneration depending on the subject's gaze direction.

[0162] The beam of light obtained by the first optical line and stimulating a portion of the retina is obtained by the method described above.

[0163] In a detailed embodiment, the light signal, more specifically the image, of the environment projected by the second optical line 18 corresponds to a portion of the environment that completes the light signal, more specifically the image, projected by the first line, such that the wearer sees a reconstructed light signal, more specifically the image, of the environment.

[0164] Furthermore, a first area 23 of the retina is stimulated with the desired light characteristics which are independent of the pupil size.

[0165] It should be noted that in such cases, the thresholds of light intensity (maximum and minimum) are given by phototoxicity standards and are further analyzed in the literature on the use of light stimulation for ophthalmological or optogenetic therapy (Yan et al., 2016; Deori, Webb, & Sliney, 2007; Sliney et al., 2005). For example, for light with a wavelength of 595 nm: The maximum light intensity at the retina is 7 mW / mm 2 (ISO 15004-2 2007;ISO 62471 2006) At the cornea (anterior), the maximum light intensity is 32 mW for any 1 mm diameter disk (ISO 15004-2 2007).

[0166] In addition, when taking into account the luminance dose limit, the retinal radiant exposure limit is 6.6 J cm for 48 hours. -2 (Luminance Dose Limits, ANSI Z136.1 2014).

[0167] According to another particular example, the visual instrument is adapted for a virtual reality instrument, the head mounted display being used for example for augmented reality, for virtual reality or for the display of cinemas.

[0168] In such a case, the optical signal projected by the second optical line 18 generally has no particular connection to the environment.

[0169] The visual instrument and methods disclosed in connection with the visual instrument 10 may be used for virtual reality or optogenetics applications. The present invention can be embodied in the following manner. (Appendix 1) a projection system (22) adapted to project a first optical signal onto a first area (23) of a retina (19) of an eye (12) of a wearer (12) of the visual instrument (10); an optical signal generator (20) for generating the first optical signal to be projected; and a waveguide (24) comprising an input coupler (24B) and an output coupler (24C), the waveguide (24) being adapted to transmit light from the input coupler (24B) to the output coupler (24C); The optical instrument (10) comprises a first optical line (16) comprising: (Appendix 2) 2. The visual instrument (10) of claim 1, further comprising a second optical line (18) having an optical system (44) adapted to project an environmental light signal onto a second region (46) of the retina of the eye (19) of the wearer (12). (Appendix 3) 3. The visual instrument (10) of claim 1 or 2, wherein the waveguide (24) is translucent, preferably transparent. (Appendix 4) 4. The visual instrument (10) according to any one of claims 1 to 3, wherein the optical signal generator (20) comprises a total internal reflection prism (30) adapted to direct the beam of incident light (30) at an angle (α), preferably said angle (α) being comprised between 20° and 40°. (Appendix 5) The visual instrument (10) according to any one of Appendices 1 to 4 when Appendices 2 and 3 are applied, wherein the two optical lines (16, 18) are arranged so that there is no overlap between the first region (23) and the second region (46). (Appendix 6) 6. The visual instrument (10) according to any one of claims 1 to 5 when referring to claim 2, wherein the two optical lines (16, 18) are arranged such that the second region (46) surrounds the first region (23). (Appendix 7) 7. The visual instrument (10) of any one of Appendices 1 to 6 when Appendices 2 and 3 are based on, wherein a main direction of light propagation (X) is defined for the waveguide (24), and the second optical line (18) and the waveguide (24) are arranged such that light in the second optical line (18) propagates along a general direction (Y) that is perpendicular to the main direction of light propagation (X) of the waveguide (24). (Appendix 8) 8. The visual instrument (10) of any one of claims 1 to 7, wherein the first optical line (16) is a bent line. (Appendix 9) The visual instrument (10) according to any one of claims 1 to 8, when referred to in claim 2, wherein the second optical line (18) is an unbent line. (Appendix 10) 10. The visual instrument (10) of claim 9, wherein the optical signal generator (20) comprises a light source (26), a first optical line (16), a collimating lens (28), a total internal reflection prism (30), a digital micromirror device (32), and a projection lens (42). (Appendix 11) 11. The visual instrument (10) of any one of claims 1 to 10, wherein the optical signal generator (20) comprises a light source (26), the light source (26) being at least one of a fiber light source and an electroluminescent diode. (Appendix 12) 12. A visual instrument (10) according to any one of claims 1 to 11, which is an instrument for optogenetics applications. (Appendix 13) 13. A visual instrument (10) according to any one of claims 1 to 12, which is a virtual reality instrument. (Appendix 14) 13. The visual instrument according to any one of claims 2 to 12, wherein the second optical line (18) is parallel to a line of sight of the eye (19) of the wearer (12). (Appendix 15) 15. The visual instrument (10) according to any one of claims 1 to 14, wherein the field of view of the projection system (22) extends from 15° to 25° along a first direction (X) and from 25° to 35° along a second direction (Y) perpendicular to the first direction (X). (Appendix 16) 1. A method for projecting an optical signal to an eye of a wearer of a visual instrument (10), comprising: a projection system (22) adapted to project a first optical signal onto a first area (23) of a retina (19) of an eye (12) of a wearer (12) of the visual instrument (10); an optical signal generator (20) for generating the first optical signal to be projected; and a waveguide (24) comprising an input coupler (24B) and an output coupler (24C), the waveguide (24) being adapted to transmit light from the input coupler (24B) to the output coupler (24C); The method comprises the steps of: (Appendix 17) 17. The method of claim 16, wherein the visual instrument (10) further comprises a second optical line (18) having an optical system (44) adapted to project an optical signal of the environment onto a second region (46) of the retina (19) of the eye (19) of the wearer (12), and comprising simultaneously projecting an optical signal by the first optical line (16) and projecting an optical signal of the environment by the second optical line (18).

Claims

1. a projection system (22) adapted to project a first optical signal onto a first area (23) of a retina (19) of an eye (12) of a wearer (12) of the visual instrument (10); an optical signal generator (20) for generating the first optical signal to be projected; a waveguide (24) comprising an input coupler (24B) and an output coupler (24C), the waveguide (24) being adapted to transmit light from the input coupler (24B) to the output coupler (24C); 1. A visual instrument (10) comprising a first optical line (16) comprising: the optical signal generator (20) comprises a light source (26), a first optical line (16), a collimating lens (28), a total internal reflection prism (30), a digital micromirror device (32), and a projection lens (42); the retina comprises a retinal implant or retinal cells genetically modified to express a light-gated ion channel protein; the light source (26) comprises a light emitting element (34) and an optical fiber (36) that conveys light to the light emitting element (34), the light emitting element (34) adapted to provide light at a wavelength capable of depolarizing cells that contain a light-activated ion channel polypeptide; The visual instrument (10) further comprises a second optical line (18) comprising an optical system (44) adapted to project an environmental light signal onto a second area (46) of the retina of the eye (19) of the wearer (12); the second optical line (18) is parallel to a line of sight of the eye (19) of the wearer (12); the second optical line (18) is an unbent line; the two optical lines (16, 18) are arranged so that there is no intersection between the first region (23) and the second region (46); A visual instrument (10), wherein the field of view provided by said projection system (22) extends from 15° to 25° along a first direction (X) and from 25° to 35° along a second direction (Y) perpendicular to said first direction (X).

2. The visual instrument (10) of claim 1, wherein the waveguide (24) is semi-transparent.

3. The visual instrument (10) of claim 1, wherein the waveguide (24) is transparent.

4. The visual instrument (10) according to any one of the preceding claims, wherein the total internal reflection prism (30) is adapted to direct an incident beam of light (31) at an angle (α).

5. The visual instrument (10) according to claim 4, wherein said angle (α) is comprised between 20° and 40°.

6. 6. The visual instrument (10) of any one of claims 1 to 5, wherein a main direction of light propagation (X) is defined for the waveguide (24), and the second optical line (18) and the waveguide (24) are arranged such that light in the second optical line (18) travels along a general direction (Y) that is perpendicular to the main direction of light propagation (X) of the waveguide (24).

7. The visual instrument (10) according to any one of the preceding claims, wherein the first optical line (16) is a bent line.

8. The visual instrument (10) according to any one of the preceding claims, wherein the input coupler (24B) and the exit coupler (24C) are manufactured from thin films of polymer.

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