NLT announces naked-eye display with better 3-D view

(Phys.org) -- NLT Technologies has announced its development of an autostereoscopic multiview display based on the success of its HxDP technology. HxDP stands for Horizontally x times Density Pixels. The company reports impressive ...

Prototype uses multi-lens display for 3-D depth (w/ video)

(PhysOrg.com) -- Numerous 3-D displays that went on parade at last month's CEATEC 2011 in Japan touted glasses-free features, but one 3-D display presentation used a technique of special interest. Researchers at Tsukuba University ...

Reach out and touch 3D characters with RePro3D (w/ video)

(PhysOrg.com) -- Lonely gamers who have felt the pain of being separated by a screen from their favorite personalities now have a way to reach out and touch their game characters, and that new way is RePro3D. A group of researchers ...

Better glasses-free 3-D: A fundamentally new approach

Nintendo's 3DS portable gaming system, the first commercial device with a glasses-free 3-D screen, has been available in the United States for barely a month, and it’s already sold more than a million units. Its three-hour ...

3D without the glasses: introducing pCubee (w/ Video)

(PhysOrg.com) -- After a wave of 3D movies such as Alice in Wonderland and Avatar, and a number of television manufacturers producing 3D TVs this year, there is growing interest in a three-dimensional viewing experience. ...

3D TV -- Without the Glasses (w/ Video)

(PhysOrg.com) -- Even with "active shutter" 3D technology for television sets, the wearing of special glasses is still required in order to get the proper experience. They aren't those red and blue or red and green 3D glasses ...

Free-floating stars in the Milky Way's bulge

The path of a light beam is bent by the presence of mass, as explained by General Relativity. A massive body can therefore act like a lens—a so called "gravitational lens"—to distort the image of an object seen behind ...

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Parallax

Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. The term is derived from the Greek παράλλαξις (parallaxis), meaning "alteration". Nearby objects have a larger parallax than more distant objects when observed from different positions, so parallax can be used to determine distances.

Astronomers use the principle of parallax to measure distances to celestial objects including to the Moon, the Sun, and to stars beyond the Solar System. For example, the Hipparcos satellite took measurements for over 100,000 nearby stars. This provides a basis for other distance measurements in astronomy, the cosmic distance ladder. Here, the term "parallax" is the angle or semi-angle of inclination between two sight-lines to the star.

Parallax also affects optical instruments such as binoculars, microscopes, and twin-lens reflex cameras that view objects from slightly different angles. Many animals, including humans, have two eyes with overlapping visual fields that use parallax to gain depth perception; this process is known as stereopsis. In computer vision the effect is used for computer stereo vision, and there is a device called a parallax rangefinder that uses it to find range, and in some variations also altitude to a target.

A simple everyday example of parallax can be seen in the dashboard of motor vehicles that use an older-style "needle" speedometer gauge. When viewed from directly in front, the speed may show exactly 60; but when viewed from the passenger seat the needle may appear to show a slightly different speed, due to the angle of viewing.

This text uses material from Wikipedia, licensed under CC BY-SA