Abstract:
The present invention is an improved visual prosthesis including a video processing unit with user controls optimized for use by blind individuals. The controls include easily identifiable shapes. The controls are programmable to provide improved usability with a simple tactile interface.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent application incorporates by reference and claims priority to U.S. Provisional Application 62/161,736, filed May 14, 2015, for Video Processing Unit for a Visual Prosthesis. This patent application is related to and incorporates by reference U.S. Pat. No. 8,798,756 for Video Processing Unit for a Visual Prosthetic Apparatus. The present invention represents a next generation improvement over the devices described in U.S. Pat. No. 8,798,756. The users controls described here are intended to work with a visual prosthesis system as described in U.S. Pat. No. 8,798,756. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present disclosure is directed to a video processing unit for a visual prosthesis, and more specifically to improved user controls for a visual prosthesis. 
       SUMMARY OF THE INVENTION 
       [0003]    The present invention is an improved visual prosthesis including a video processing unit with user controls optimized for use by blind individuals. The controls include easily identifiable shapes. The controls are programmable to provide improved usability with a simple tactile interface. A programmable slider serves a variety of input functions. 
     
    
     
       DESCRIPTION OF THE FIGURES OF THE DRAWING 
         [0004]      FIG. 1  is a top right perspective view of the video processing unit. 
           [0005]      FIG. 2  is a front view of the video processing unit. 
           [0006]      FIG. 3  is a rear view of the video processing unit. 
           [0007]      FIG. 4  is a right side view of the video processing unit. 
           [0008]      FIG. 5  is a left side view of the video processing unit. 
           [0009]      FIG. 6  is a top view of the video processing unit. 
           [0010]      FIG. 7  is a bottom view of the video processing unit. 
           [0011]      FIG. 8  is a perspective view of the glasses. 
           [0012]      FIG. 9  is a perspective view of the implanted portion of the visual prosthesis. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0013]    Referring to  FIGS. 1-7 , user input controls on the housing of the video processing unit  2  include a power button  4  and a mute button  12  on the top of video processing unit  2  housing. The power button is depressed for a predetermined time, about a second, to turn the video processor  2  on or off. The mute  12  button mutes audio feedback. On the face of the video processing unit  2  housing is an analog slider  8 . In the default mode, the analog slider  8  controls brightness. The analog slider is a potentiostat that returns its value to the microprocessor in the video processing unit  2  through an analog to digital converter. It can be programmed for any function. Alternate functions can include gain, sensitivity (including separate indoor and outdoor settings), exposure, contrast or zoom (zoom in, zoom out, and 1-1), total brightness limit (useful for photo phobic patients) and frequency of stimulation. 
         [0014]    Below the analog slider  8  is a three position selector switch  10  to choose between programmable options. The three position selector switch includes tactile marks  11  to aid blind users. The three position selector switch is also programmable for function. The position selector switch can select between predefined filters or alter the function of the analog slider  8  as discussed above. Below the three position selector switch  10  is an invert switch  6 . The invert switch  6  inverts the image, light is dark and dark is light. All of the buttons are programmable to multiple functions. As an example, the power button  4  and the mute button  12  can be programmed as yes and no responses to menu functions. An additional programmable button  14  is on the bottom of the housing. The battery cover  22  is also on the bottom of the housing and includes tactile markings to aid the blind user. 
         [0015]    The buttons are arranged to maximize use by blind users. Inset  16  surrounds the analog slider  8 , thee position selector  10  and invert switch  6 . This allows a user to quickly indentify the front and back of the video processing unit  2  housing and to find the location of user controls. Top and bottom orientation is achieved by the location of the data cable  18  in the top. The data cable  18  is connected to the top via the data cable connector  24 . The video processing unit  2  further includes a speaker  20  on the back side opposite the user controls. The speaker  20  can be used for informative signals like those associated with turning on or off, error warning or announcements supporting use of the menu system. 
         [0016]    Referring to  FIG. 8 , the glasses  25  may comprise, for example, a frame  31  holding a camera  32 , an external coil  34  and a mounting system  36  for the external coil  34 . The mounting system  36  may also enclose the RF circuitry. In this configuration, the video camera  32  captures live video. The video signal is sent to the Video Processing Unit  2  (shown in  FIGS. 1-7 ), which processes the video signal and subsequently transforms the processed video signal into electrical stimulation patterns or data. The electrical stimulation data are then sent to the external coil  34  that sends both data and power via radio-frequency (RF) telemetry to the coil  116  of the retinal stimulation system  100 , shown in  FIG. 9 . The coil  116  receives the RF commands which control the application specific integrated circuit (ASIC) inside the electronics package  114 , which in turn delivers stimulation to the retina of the subject via a thin film electrode array (TFEA)  112 . In one aspect of an embodiment, light amplitude is recorded by the camera  32 . The VPU  2  may use a logarithmic encoding scheme to convert the incoming light amplitudes into the electrical stimulation patterns or data. These electrical stimulation patterns or data may then be passed on to the Retinal Stimulation System  100 , which results in the retinal cells being stimulated via the electrodes in the electrode array  110  (shown in  FIG. 9 ). In one exemplary embodiment, the electrical stimulation patterns or data being transmitted by the external coil  34  is binary data. The external coil  34  may contain a receiver and transmitter antennae and a radio-frequency (RF) electronics card for communicating with the internal coil  116 . 
         [0017]      FIG. 9  shows a perspective view of the implanted portion of the preferred visual prosthesis. A flexible circuit  112  includes a flexible circuit electrode array  110  which is mounted by a retinal tack (not shown) or similar means to the epiretinal surface. The flexible circuit electrode array  110  is electrically coupled by a flexible circuit cable  112 , which pierces the sclera and is electrically coupled to an electronics package  114 , external to the sclera. 
         [0018]    The electronics package  114  is electrically coupled to a secondary inductive coil  116 . Preferably the secondary inductive coil  116  is made from wound wire. Alternatively, the secondary inductive coil  116  may be made from a flexible circuit polymer sandwich with wire traces deposited between layers of flexible circuit polymer. The secondary inductive coil receives power and data from a primary inductive coil  34 , which is external to the body. The electronics package  114  and secondary inductive coil  116  are held together by the molded body  118 . The molded body  18  holds the electronics package  114  and secondary inductive coil  116  end to end. The molded body  118  holds the secondary inductive coil  116  and electronics package  114  in the end to end orientation and minimizes the thickness or height above the sclera of the entire device. The molded body  118  may also include suture tabs  120 . The molded body  118  narrows to form a strap  122  which surrounds the sclera and holds the molded body  118 , secondary inductive coil  116 , and electronics package  114  in place. The molded body  118 , suture tabs  120  and strap  122  are preferably an integrated unit made of silicone elastomer. Silicone elastomer can be formed in a pre-curved shape to match the curvature of a typical sclera. However, silicone remains flexible enough to accommodate implantation and to adapt to variations in the curvature of an individual sclera. The secondary inductive coil  116  and molded body  118  are preferably oval shaped. A strap  122  can better support an oval shaped coil. It should be noted that the entire implant is attached to and supported by the sclera. An eye moves constantly. The eye moves to scan a scene and also has a jitter motion to improve acuity. Even though such motion is useless in the blind, it often continues long after a person has lost their sight. By placing the device under the rectus muscles with the electronics package in an area of fatty tissue between the rectus muscles, eye motion does not cause any flexing which might fatigue, and eventually damage, the device. 
         [0019]    The molded body  118  narrows into a fin tail  124  at the strap  122 . When implanting the visual prosthesis, it is necessary to pass the strap  122  under the eye muscles to surround the sclera. The secondary inductive coil  116  and molded body  118  must also follow the strap  122  under the lateral rectus muscle on the side of the sclera. The implanted portion of the visual prosthesis is very delicate. It is easy to tear the molded body  118  or break wires in the secondary inductive coil  116 . In order to allow the molded body  118  to slide smoothly under the lateral rectus muscle, the molded body  118  is shaped in the form of a fan tail  124  on the end opposite the electronics package  114 . 
         [0020]    Accordingly, what has been shown is an improved visual prosthesis. While the invention has been described by means of specific embodiments and applications thereof, it is understood that numerous modifications and variations could be made thereto by those skilled in the art without departing from the spirit and scope of the invention. It is therefore to be understood that within the scope of the claims, the invention may be practiced otherwise than as specifically described herein.