Daniel Kish from california who has been blind since his child-

hood has perfected a form of echolocation, using echoes to

build a mental picture of his surroundings.

But in most of the cases this form of active echolocation is

discouraged for the blinds as it draws undue attention to

oneself

IDEA

Rather than relying solely on sound waves, if a device that can act as a virtual eye and probably perform similar function of a real eye ,then it would be more reliable as emitting sounds even of other frequencies inaudible to humans can create disturbance to other forms of life that can detect them. So a spectacle with sensors that can perceive the visual rays with an additional hearing aid that can incorporate the sound emitted, with the visuals and create a 3D image in the visual cortex of the brain by means of leads attached to the occipital region of brain that carry the signals there, would help out many untrained blind people and at places where they can't make clicks or taps (libraries) to browse objects.

Echolocating animals emit calls out to the environment and listen to the echoes

of those calls that return from various objects in the environment. 

They use these echoes to locate, range, and identify the objects.

Echolocation is used for navigation and for foraging (or hunting) in various

environments.

IDEA

Animals emit sounds at 100-200 clicks per sec but humans can only produce 

2-3 clicks per sec . Therefore we can develope such device which can emit sounds that match up with animals such as bats. Such device should emit an inaudible sound which once reflected by  objects in environment  can be heard only by  person who is using that device through custom earphones to avoid drawing negative attention if continuous clicks are produced by mouth. After listening the reflected sound one can build a mental picture of the surrounding by practicing this technique.

The theory behind both Ultra cane and Ultra bike is the use of an Ultrasound sensor kit that detects the reflected ultrasound waves from the objects in the surrounding, so that the visually impaired can have an idea about the obstacles in their path.

Eventhough the Ultrabike is not suitable for use on the road, as drivers assume that cyclists have complete vision, its an amazing way of helping the blind experience the feeling of cycling, that cannot be experienced by them if not for this.

WHAT MORE CAN BE DONE?

Instead of Ultrasound waves, another harmless electromagnetic wave can be used in place. These waves, when reflected can be detected by a sensor that is placed close to one's face. This sensor can send vibrations to the Brain depending on the intensity of the reflected wave.The Brain creates a vague image of the surrounding depending on the intensity, speed and phase of waves.