EyeTap

An EyeTap is a device that is worn in front of the eye that acts as a camera to record the scene available to the eye as well as a display to superimpose computer-generated imagery on the original scene available to the eye. This structure allows the user's eye to operate as both a monitor and a camera as the EyeTap intakes the world around it and augments the image the user sees allowing it to overlay computer-generated data over top of the normal world the user would perceive. The EyeTap is a hard technology to categorize under the three main headers for wearable computing (constancy, augmentation, mediation) for while it is in theory a constancy technology in nature it also has the ability to augment and mediate the reality the user perceives.

In order to capture what the eye is seeing as accurately as possible, an EyeTap uses a beam splitter to send the same scene (with reduced intensity) to both the eye and a camera. The camera then digitizes the reflected image of the scene and sends it to a computer. The computer processes the image and then sends it to a projector. The projector sends the image to the other side of the beam splitter so that this computer-generated image is reflected into the eye to be superimposed on the original scene. Stereo EyeTaps modify light passing through both eyes, but many research prototypes (mainly for reasons of ease of construction) only tap one eye.

EyeTap is also the name of an organization founded by inventor Steve Mann to develop and promote EyeTap-related technologies such as wearable computers.

An EyeTap is somewhat like a head-up display (HUD). The important difference is that the scene available to the eye is also available to the computer that projects the head-up display. This enables the EyeTap to modify the computer generated scene in response to the natural scene. One use, for instance, would be a sports EyeTap: here the wearer, while in a stadium, would be able to follow a particular player in a field and have the EyeTap display statistics relevant to that player as a floating box above the player. Another practical use for the EyeTap would be in a construction yard as it would allow the user to reference the blueprints, especially in a 3D manner, to the current state of the building, display a list of current materials and their current locations as well perform basic measurements. Or, even in the business world, the EyeTap has great potential, for it would be capable of delivering to the user constant up to date information on the stock market, the user's corporation, and meeting statuses. On a more day-to-day basis some of Steve Mann's first uses for the technology was using it to keep track of names of people and places, his to-do lists, and keeping track of his other daily ordeals. The EyeTap Criteria are an attempt to define how close a real, practical device comes to such an ideal. EyeTaps could have great use in any field where the user would benefit from real-time interactive information that is largely visual in nature. This is sometimes referred to as computer-mediated reality, commonly known as augmented reality.

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