fig1 schematically shows an nt - ssd 20 providing non - tactile corneal stimulation optionally to a vision compromised person 200 responsive to an environment represented by a rectangle 100 , in accordance with an embodiment of the invention . nt - ssd 20 optionally comprises right eye and left eye cameras 41 and 42 respectively , right eye and left eye laser stimulators 51 and 52 respectively , and right eye and left eye gaze trackers 31 and 32 respectively , optionally mounted to a visor 60 . right and left eye cameras 41 and 42 optionally acquire right and left images of environment 100 substantially from the perspectives of right and left eyes 201 and 202 of person 200 . right and left laser stimulators 51 and 52 receive data from cameras 41 and 42 associated with the right and left images and direct laser beams 53 and 54 respectively to illuminate and stimulate a raster of regions on the corneas , and optionally sclera , of eyes 201 and 202 to generate ntcs neural images responsive to the received data that may provide a sense of depth or perspective . by way of example , an inset 300 shows an enlarged portion of the cornea and portions of the sclera of right eye 201 of person 200 and a raster 301 of regions 310 of the cornea and sclera that are stimulated by laser beam 51 . in an embodiment of the invention locations of stimulated regions 310 of the cornea and / or sclera are registered to a location of the person &# 39 ; s pupil and / or gaze direction and or location of a fixed feature on the eyeball surface provided by gaze tracker 31 . unless otherwise indicated or obvious from the context , referencing a location of a stimulated region to a gaze direction includes referencing the location to the pupil , gaze direction , or fixed feature . referencing a location of a stimulated region to a gaze direction may , as discussed by way of example below , be advantageous for stimulating regions of the cornea appropriate to provide person 200 with an ntcs image that may satisfactorily track features in environment 100 as the person moves , changes gaze direction or the features move . gaze trackers 31 and 32 may determine gaze direction using any of various methods known in the art , and may for example determine gaze direction responsive to imaging eye glints and / or purkinje reflections or by determining a direction of a magnetic dipole field that the eye generates . in referencing locations for stimulation , laser stimulator 51 or 52 or gaze tracker 31 or 32 may use a reference coordinate system , such as a coordinate system having x and y axes , that the laser stimulator or its associated gaze tracker establishes . optionally the reference coordinate system has x and y axes and laser stimulator 51 or 52 may stimulate the eye as a function of x and y coordinates referenced to the coordinate system . optionally , an origin of the coordinate system is the center of the pupil . optionally , the coordinate system has x and y axes that are substantially fixed relative to the structure of the eye and do not move relative to the surface of the eye with movement of the eye in its socket . fixed x and y axes may be established responsive to a fixed feature of the eye , such as a mark on the eye or an asymmetry of the eye . a fixed coordinate system may be a virtual fixed coordinate system having axes whose directions are determined from physiological knowledge as to how the musculature that controls motion of an eye in its socket would move fixed features of the eye as the musculature moves the eye . whereas in fig1 nt - ssd 20 comprises laser stimulators 51 and 52 , practice of the invention is not limited to using laser stimulators to generate ntcs neural signals . for example , fig2 schematically shows an nt - ssd 120 comprising right and left acoustic stimulators 151 and 152 comprising phased arrays 160 for generating focused acoustic beams 161 and 162 to stimulate regions of the right and left eyes 201 and 202 respectively , of person 200 to generate ntcs neural signals and images . it also noted that whereas environment imagers in fig1 and 2 are indicated as comprising cameras 41 and 42 , which acquire optical images of the environment of person 200 , in accordance with an embodiment of the invention environment imagers that comprise acoustic imagers may be used to acquire images of a person &# 39 ; s environment to provide data for generating ntcs neural signals . and whereas nt - ssd 20 and 120 comprise right and left environment imagers 41 and 42 and stimulators 51 , 52 and 151 , 152 respectively and are indicated as possibly providing perspective ntcs neural images , an embodiment of the invention may of course have only one environment imager and optionally only one stimulator . it is further noted that the placement of environment imagers and stimulators in fig1 and 2 may of course be different from placement of the imagers and stimulators shown in fig1 and 2 . in the figures , the imagers and / or stimulators may block portions of the field of view ( fov ) of person 200 . whereas for a blind person blockage of the field of view may be irrelevant , for a sighted person using an nt - ssd for receiving data in accordance with an embodiment of the invention , blockage of the person &# 39 ; s field of view may be undesirable . for such cases , environment imagers may be located outside of the person &# 39 ; s fov or at a periphery of the fov . for example , environment imagers may be located on sides of visor 60 and stimulators may be mounted off - center , or substantially off center from a central region of the person &# 39 ; s fov when the person is looking straight ahead relative to head orientation . furthermore , whereas components of nt - ssd 20 and 120 are shown mounted to a visor , components of an nt - ssd are not necessarily mounted on a visor or directed to image an environment in front of person 200 . for example , cameras 41 and 42 may be mounted on a person &# 39 ; s chest or may be mounted to the back of a person &# 39 ; s head or the person &# 39 ; s back to provide images of an environment behind the person . in the description and claims of the present application , each of the verbs , “ comprise ” “ include ” and “ have ”, and conjugates thereof , are used to indicate that the object or objects of the verb are not necessarily a complete listing of components , elements or parts of the subject or subjects of the verb . descriptions of embodiments of the invention in the present application are provided by way of example and are not intended to limit the scope of the invention . the described embodiments comprise different features , not all of which are required in all embodiments of the invention . some embodiments utilize only some of the features or possible combinations of the features . variations of embodiments of the invention that are described , and embodiments of the invention comprising different combinations of features noted in the described embodiments , will occur to persons of the art . the scope of the invention is limited only by the claims .
there is therefore provided in accordance with an embodiment of the invention , apparatus for providing a person with neural signals responsive to features of an environment , the apparatus comprising : an environment imager that acquires an image of a region of the person &# 39 ; s environment ; and a non - contact corneal neural stimulator that stimulates nerve endings in the cornea of the person &# 39 ; s eye responsive to the image of the environment .