Audio Sight

Although light and sound are differing types of phenomena, they are both propogated by waves and the frequencies of the waves have corresponding frequencies. For example, the musical note "A" in the fourth octave is a sound frequency of 440 Hz, and 880 Hz in the next octave etc. This corresponds to a visible light frequency of around 480 Thz, which is a red-orange color.

I propose a device consisting of a camera (or two cameras if it would work) that takes an image and converts it to a unique blip of audio sound. For example, if an image is obtained at a resolution of, say, 160x100 pixels, it could be translated to a short screech of audio in much the same way that a modem translates data to audio for transmission over a phone line. 160x100 pixels with 256 possible colors would be 128,000 bits of information per second, which is slightly higher than double the rate of a 56 Kbps modem.

I don't know if it's possible to modulate data to audio at that high of a rate, but my understanding is that modems topped out at 56 Kbps not because of limitations with the modulation technology but due to limitations of phone lines and FCC regulations.

The sound of the image would be basically a noisy screech, but I postulate that if someone used the device for long enough, the brain will adapt and begin to extract the patterns from the data and provide an alternative to sight.

If two of the devices were used together, one for each ear, it may be possible to 'see' in stereo with depth perception. This wouldn't be a great enough technology to allow someone to drive, read, etc., but I can see it being very helpful with walking around in busy areas.

Depending on the limitations of the concept of audio wave modulation, it may even be possible to raise the resolution and frame rate, although I do suspect there is a definite limit.