20-06-2012, 01:59 PM
Optical camouflage
[attachment=24903]
Abstract
Invisibility, an impossible dream depicted in science fiction. Not really, actually optical camouflage is old hat. We live in time where a stealth suit was called the coolest invention of 2003 by Time magazine.
Professors Inami, Seguchi and Tachi at the University of Tokyo invented a transparent cloak by projecting a background image taken by a video camera onto the masked object. By this you can observe the masked object just as if it were virtually transparent.
This paper describes a kind of active camouflage system named optical camouflage. The camouflaging technology uses what is termed as “retro-reflective material” to do its work. Tiny light-reflecting beads display what is effectively “behind” the garment. Optical camouflage uses the retro-reflective projection technology, a projection-based augmented-reality system composed of a projector with a small iris and a retro-reflective screen. The object that needs to be made transparent is painted or covered with retro-reflective material. Then a projector projects the background image on it making the masking object virtually transparent.
Introduction
Invisibility has been on humanity's wish list at least since Amon-Ra, a diety who could disappear and reappear at will, joined the Egyptian pantheon in 2008 BC. With rec ent advances in optics and computing, however, this elusive goal is no longer purely imaginary. Last spring, Susumu Tachi, an engineering professor at the University of Tokyo, demonstrated a crude invisibility cloak. Through the clever application of some dirt-cheap technology, the Japanese inventor has brought personal invisibility a step closer to reality.
Tachi's cloak - a shiny raincoat that serves as a movie screen, showing imagery from a video camera positioned behind the wearer - is more gimmick than practical prototype. Nonetheless, from the right angle and under controlled circumstances, it does make a sort of ghost of the wearer. And, unlike traditional camouflage, it's most effective when either the wearer or the background is moving (but not both).
What is camouflage?
Camouflage, also known as cryptic coloration, is the method which allows an otherwise visible organism or object to remain indiscernible from the surrounding environment. Examples include a tiger's stripes and the battledress of a modern soldier. Camouflage is a form of deception. The word camouflage comes from the French word 'camoufler' meaning 'to disguise'.
Active camouflage
Active camouflage or adaptive camouflage, is a group of camouflage technologies which allow an object to blend into its surroundings by use of panels or coatings capable of altering their appearance, color, luminance and reflective properties. Active camouflage has the potential to achieve perfect concealment from visual detection.
Active camouflage differs from conventional means of concealment in two important ways. First, it makes the object appear not merely similar to its surroundings, but invisible through the use of perfect mimicry. Second, active camouflage changes the appearance of the object in real time. Ideally, active camouflage mimics nearby objects as well as objects as distant as the horizon. The effect should be similar to looking through a pane of glass, making the camouflaged object practically invisible.
Active camouflage has its origins in the diffused lighting camouflage first tested on Canadian Navy corvettes during World War II, and later in the armed forces of the United Kingdom and the United States of America.
Current systems began with a United States Air Force program which placed low-intensity blue lights on aircraft. As night skies are not pitch black, a 100 percent black-colored aircraft might be rendered visible. By emitting a small amount of blue light, the aircraft blends more effectively into the night sky.
Active camouflage is poised to develop at a rapid pace with the development of organic light-emitting diodes (OLEDs) and other technologies which allow for images to be projected onto irregularly-shaped surfaces. With the addition of a camera, an object may not be made completely invisible, but may in theory mimic enough of its surrounding background to avoid detection by the human eye as well as optical sensors. As motion may still be noticeable, an object might not be rendered undetectable under this circumstance but potentially more difficult to hit.
Optical camouflage
Optical camouflage is a kind of active camouflage which completely envelopes the wearer. It displays an image of the scene on the side opposite the viewer on it, so that the viewer can "see through" the wearer, rendering the wearer invisible.
Outside of fiction, the concept exists only in theory and in proof-of-concept prototypes, although many experts consider it technically feasible. In 2003, three professors at University of Tokyo — Susumu Tachi, Masahiko Inami and Naoki Kawakami — created a prototypical camouflage system in which a video camera takes a shot of the background and displays it on the cloth using an external projector. The same year Time magazine named it the coolest invention of 2003. With flexible electronics such as a flexible liquid crystal display that would permit display of the background image by the material itself, this form of optical camouflage may closely resemble its fictional counterparts.
Introduction to how invisibility clock works
Optical camouflage delivers a similar experience to Harry Potter's invisibility cloak, but using it requires a slightly more complicated arrangement. First, the person who wants to be invisible (let's call her Person A) dons a garment that resembles a hooded raincoat. The garment is made of a special material that we'll examine more closely in a moment. Next, an observer (Person B) stands before Person A at a specific location. At that location, instead of seeing Person A wearing a hooded raincoat, Person B sees right through the cloak, making Person A appears to be invisible.
Principle of working
Optical camouflage doesn't work by way of magic. It works by taking advantage of something called augmented-reality technology -- a type of technology that was first pioneered in the 1960s by Ivan Sutherland and his students at Harvard University and the University of Utah.
Augmented-reality systems add computer-generated information to a user's sensory perceptions. Imagine, for example, that you're walking down a city street. As you gaze at sites along the way, additional information appears to enhance and enrich your normal view. Perhaps it's the day's specials at a restaurant or the show times at a theater or the bus schedule at the station. What's critical to understand here is that augmented reality is not the same as virtual reality. While virtual reality aims to replace the world, augmented reality merely tries to supplement it with additional, helpful content.
[attachment=24903]
Abstract
Invisibility, an impossible dream depicted in science fiction. Not really, actually optical camouflage is old hat. We live in time where a stealth suit was called the coolest invention of 2003 by Time magazine.
Professors Inami, Seguchi and Tachi at the University of Tokyo invented a transparent cloak by projecting a background image taken by a video camera onto the masked object. By this you can observe the masked object just as if it were virtually transparent.
This paper describes a kind of active camouflage system named optical camouflage. The camouflaging technology uses what is termed as “retro-reflective material” to do its work. Tiny light-reflecting beads display what is effectively “behind” the garment. Optical camouflage uses the retro-reflective projection technology, a projection-based augmented-reality system composed of a projector with a small iris and a retro-reflective screen. The object that needs to be made transparent is painted or covered with retro-reflective material. Then a projector projects the background image on it making the masking object virtually transparent.
Introduction
Invisibility has been on humanity's wish list at least since Amon-Ra, a diety who could disappear and reappear at will, joined the Egyptian pantheon in 2008 BC. With rec ent advances in optics and computing, however, this elusive goal is no longer purely imaginary. Last spring, Susumu Tachi, an engineering professor at the University of Tokyo, demonstrated a crude invisibility cloak. Through the clever application of some dirt-cheap technology, the Japanese inventor has brought personal invisibility a step closer to reality.
Tachi's cloak - a shiny raincoat that serves as a movie screen, showing imagery from a video camera positioned behind the wearer - is more gimmick than practical prototype. Nonetheless, from the right angle and under controlled circumstances, it does make a sort of ghost of the wearer. And, unlike traditional camouflage, it's most effective when either the wearer or the background is moving (but not both).
What is camouflage?
Camouflage, also known as cryptic coloration, is the method which allows an otherwise visible organism or object to remain indiscernible from the surrounding environment. Examples include a tiger's stripes and the battledress of a modern soldier. Camouflage is a form of deception. The word camouflage comes from the French word 'camoufler' meaning 'to disguise'.
Active camouflage
Active camouflage or adaptive camouflage, is a group of camouflage technologies which allow an object to blend into its surroundings by use of panels or coatings capable of altering their appearance, color, luminance and reflective properties. Active camouflage has the potential to achieve perfect concealment from visual detection.
Active camouflage differs from conventional means of concealment in two important ways. First, it makes the object appear not merely similar to its surroundings, but invisible through the use of perfect mimicry. Second, active camouflage changes the appearance of the object in real time. Ideally, active camouflage mimics nearby objects as well as objects as distant as the horizon. The effect should be similar to looking through a pane of glass, making the camouflaged object practically invisible.
Active camouflage has its origins in the diffused lighting camouflage first tested on Canadian Navy corvettes during World War II, and later in the armed forces of the United Kingdom and the United States of America.
Current systems began with a United States Air Force program which placed low-intensity blue lights on aircraft. As night skies are not pitch black, a 100 percent black-colored aircraft might be rendered visible. By emitting a small amount of blue light, the aircraft blends more effectively into the night sky.
Active camouflage is poised to develop at a rapid pace with the development of organic light-emitting diodes (OLEDs) and other technologies which allow for images to be projected onto irregularly-shaped surfaces. With the addition of a camera, an object may not be made completely invisible, but may in theory mimic enough of its surrounding background to avoid detection by the human eye as well as optical sensors. As motion may still be noticeable, an object might not be rendered undetectable under this circumstance but potentially more difficult to hit.
Optical camouflage
Optical camouflage is a kind of active camouflage which completely envelopes the wearer. It displays an image of the scene on the side opposite the viewer on it, so that the viewer can "see through" the wearer, rendering the wearer invisible.
Outside of fiction, the concept exists only in theory and in proof-of-concept prototypes, although many experts consider it technically feasible. In 2003, three professors at University of Tokyo — Susumu Tachi, Masahiko Inami and Naoki Kawakami — created a prototypical camouflage system in which a video camera takes a shot of the background and displays it on the cloth using an external projector. The same year Time magazine named it the coolest invention of 2003. With flexible electronics such as a flexible liquid crystal display that would permit display of the background image by the material itself, this form of optical camouflage may closely resemble its fictional counterparts.
Introduction to how invisibility clock works
Optical camouflage delivers a similar experience to Harry Potter's invisibility cloak, but using it requires a slightly more complicated arrangement. First, the person who wants to be invisible (let's call her Person A) dons a garment that resembles a hooded raincoat. The garment is made of a special material that we'll examine more closely in a moment. Next, an observer (Person B) stands before Person A at a specific location. At that location, instead of seeing Person A wearing a hooded raincoat, Person B sees right through the cloak, making Person A appears to be invisible.
Principle of working
Optical camouflage doesn't work by way of magic. It works by taking advantage of something called augmented-reality technology -- a type of technology that was first pioneered in the 1960s by Ivan Sutherland and his students at Harvard University and the University of Utah.
Augmented-reality systems add computer-generated information to a user's sensory perceptions. Imagine, for example, that you're walking down a city street. As you gaze at sites along the way, additional information appears to enhance and enrich your normal view. Perhaps it's the day's specials at a restaurant or the show times at a theater or the bus schedule at the station. What's critical to understand here is that augmented reality is not the same as virtual reality. While virtual reality aims to replace the world, augmented reality merely tries to supplement it with additional, helpful content.