L'invention concerne un procede et un appareil de determination d'intensites et de longue... more L'invention concerne un procede et un appareil de determination d'intensites et de longueurs d'onde maximales de lumiere. L'appareil comprend une ou plusieurs paires de modules detecteurs destines a detecter la lumiere, un premier module detecteur d'une paire etant concu pour detecter une premiere intensite de la lumiere dans une premiere plage de longueurs d'onde predeterminee avec une premiere sensibilite spectrale donnee, et un deuxieme module detecteur d'une paire etant concu pour detecter une deuxieme intensite de la lumiere dans la premiere plage de longueurs d'onde predeterminee avec une deuxieme sensibilite spectrale donnee. L'appareil comprend en outre un systeme de traitement relie de facon fonctionnelle a une ou a plusieurs desdites paires de modules detecteurs. Ce systeme de traitement est concu pour determiner l'intensite et la longueur d'onde maximale pour chacune desdites plages de longueurs d'onde (une ou plusieurs) pre...
L'invention concerne une source lumineuse, un procede, un support de stockage lisible par ord... more L'invention concerne une source lumineuse, un procede, un support de stockage lisible par ordinateur et un produit de programme informatique destines a optimiser au moins une de ses caracteristiques d'eclairage. Plus precisement, l'invention concerne une source lumineuse comprenant au moins quatre elements, groupes ou reseaux electroluminescents, chacun presentant un spectre d'emission predefini correspondant qui, combines en fonction d'un rapport d'intensite donne, produisent un eclairage a une certaine temperature de couleur. Cette source lumineuse peut comprendre un module de selection interne et/ou interne pour choisir une ou plusieurs caracteristiques d'eclairage a optimiser, un module informatique interne et/ou externe pour optimiser des parametres d'entrainement de la source lumineuse pour produire les caracteristiques d'eclairage optimisees choisies. Ladite source d'eclairage peut etre eventuellement câblee pour fonctionner selon des p...
The IES BUG rating system is useful for classifying outdoor luminaires when considering light tre... more The IES BUG rating system is useful for classifying outdoor luminaires when considering light trespass, sky glow, and glare in accordance with the Joint IDA-IES Model Lighting Ordinance (MLO). However, there are limits to what can be measured in the laboratory. Luminaires with uplight ratings of U0 or U1 or a glare rating of G0 may require further analysis when comparing manufacturers’ products.
Apparatus for controlling a luminaire (100; 200) including one or more elements (130) emitting en... more Apparatus for controlling a luminaire (100; 200) including one or more elements (130) emitting enuno light or more colors, supplied each of one or more elements (130) emitting light with corrienteelectrica to produce light, comprising said aparatoa ) means for adjusting the supply to one power or more elements (130) emitting light usandomodulacion pulse width modulation or pulse code, each of said width modulacionpor and pulse code modulation pulse cycle pulse; b) means for modulating a pulse width for each pulse cycle, thereby increasing the resolution decontrol one or more elements (130) emitting light; characterized in that said apparatus it comprises unaparato width modulation pulse extended to transform a signal of (N + M) bits in a flujode 2M words width N bits for a total of 2M pulse cycles, the apparatus comprising demodulation width Extended pulse: c) means for receiving the signal (N + M) bits, d) means for dividing the signal (N + M) bits in a portion of N bits and a port...
Radiative flux transfer between Lambertian surfaces can be described in terms of linear resistive... more Radiative flux transfer between Lambertian surfaces can be described in terms of linear resistive networks with voltage sources. This thesis examines how these "radiative transfer networks" provide a physical interpretation for the eigenvalues and eigenvectors of form factor matrices. This leads to a novel approach to photorealistic image synthesis and radiative flux transfer analysis called eigenvector radiosity.
• here are two basic approaches to generating photorealistic images in computer graphics. The fir... more • here are two basic approaches to generating photorealistic images in computer graphics. The first approach involves ray tracing techniques; the second approach is radiosity. Radiosity is in some ways the complement of ray tracing. While ray tracing techniques excel in the rendition of point light sources, specular reflections and refl'action effects, radiosity meth~ ods accurately model area light sources, diffuse reflections, color bleeding effects and realistic shadows. Together, they offer rendering capabilities beyond those available from ray tracing or radiosity alone. The essence of ray tracing technique is the geometric ray. We model rays of light that emanate from the eye and propagate through the environment. We can create synthetic images by calculating their interaction (that is, reflection, refraction, absorption and so forth) with objects in the environment. In this sense, we can see that ray tracing models objects, or at least our perception of them, from a given viewpoint. Radiosity offers a fundamentally different approach. Given a complex environment , we can subdivide each surface into a mesh of polygons called patches. By modeling some of these patches as emitters, we can determine the inter-reflections, or multiple bounces, of light within the environment on a patch-by-patch basis. From these inter-reflections come the indirect lighting effects, gradations and soft shadows that can impart such a dramatic sense of realism to radiosity-based images. It has been argued that ray tracing offers view-dependent solutions, while those of radiosity are view-independent. That is, once the radiosity equation has been solved for a given environment , different views can be rendered very quickly. This, however, is a fallacy. Radiosity's view independence applies only to ideal diffuse (or Lambertian) surfaces. As Ward (1994) so eloquently reminded us, stochastic ray tracing techniques such as those used in RADIANCE are equally capable of view independence under these conditions. Radiosity is more than this, however. Whereas ray tracing models objects, radiosity models light. That is, radiosity models light as a five-dimensional scalar "photic field" that permeates any luminous environment (Moon and Spencer 198l). This field can be thought of as an infinite number of rays, each with its own measurable photometric brightness (or, more properly , luminance) at each point in space along its length. The objects in the environment become little more than the field's boundary conditions. Light as a five-dimensional scalar field? In terms of photorealistic images, this concept may have little to recommend it. …
The present invention provides an integrated independent lighting module, which may be used alone... more The present invention provides an integrated independent lighting module, which may be used alone or in combination with other modules, to produce white light of any other color within or chromatography. Each module includes one or more light emitting elements, and drive control systems, feedback systems, thermal management system, an optical system and a communication system can be optionally in communication between the modules and / or other control systems. Depending on the structure, the illumination module may operate autonomously, or may be based on an internal signal, or both signals or signal received from the outside to determine its function.
L'invention concerne un procede et un appareil de determination d'intensites et de longue... more L'invention concerne un procede et un appareil de determination d'intensites et de longueurs d'onde maximales de lumiere. L'appareil comprend une ou plusieurs paires de modules detecteurs destines a detecter la lumiere, un premier module detecteur d'une paire etant concu pour detecter une premiere intensite de la lumiere dans une premiere plage de longueurs d'onde predeterminee avec une premiere sensibilite spectrale donnee, et un deuxieme module detecteur d'une paire etant concu pour detecter une deuxieme intensite de la lumiere dans la premiere plage de longueurs d'onde predeterminee avec une deuxieme sensibilite spectrale donnee. L'appareil comprend en outre un systeme de traitement relie de facon fonctionnelle a une ou a plusieurs desdites paires de modules detecteurs. Ce systeme de traitement est concu pour determiner l'intensite et la longueur d'onde maximale pour chacune desdites plages de longueurs d'onde (une ou plusieurs) pre...
L'invention concerne une source lumineuse, un procede, un support de stockage lisible par ord... more L'invention concerne une source lumineuse, un procede, un support de stockage lisible par ordinateur et un produit de programme informatique destines a optimiser au moins une de ses caracteristiques d'eclairage. Plus precisement, l'invention concerne une source lumineuse comprenant au moins quatre elements, groupes ou reseaux electroluminescents, chacun presentant un spectre d'emission predefini correspondant qui, combines en fonction d'un rapport d'intensite donne, produisent un eclairage a une certaine temperature de couleur. Cette source lumineuse peut comprendre un module de selection interne et/ou interne pour choisir une ou plusieurs caracteristiques d'eclairage a optimiser, un module informatique interne et/ou externe pour optimiser des parametres d'entrainement de la source lumineuse pour produire les caracteristiques d'eclairage optimisees choisies. Ladite source d'eclairage peut etre eventuellement câblee pour fonctionner selon des p...
The IES BUG rating system is useful for classifying outdoor luminaires when considering light tre... more The IES BUG rating system is useful for classifying outdoor luminaires when considering light trespass, sky glow, and glare in accordance with the Joint IDA-IES Model Lighting Ordinance (MLO). However, there are limits to what can be measured in the laboratory. Luminaires with uplight ratings of U0 or U1 or a glare rating of G0 may require further analysis when comparing manufacturers’ products.
Apparatus for controlling a luminaire (100; 200) including one or more elements (130) emitting en... more Apparatus for controlling a luminaire (100; 200) including one or more elements (130) emitting enuno light or more colors, supplied each of one or more elements (130) emitting light with corrienteelectrica to produce light, comprising said aparatoa ) means for adjusting the supply to one power or more elements (130) emitting light usandomodulacion pulse width modulation or pulse code, each of said width modulacionpor and pulse code modulation pulse cycle pulse; b) means for modulating a pulse width for each pulse cycle, thereby increasing the resolution decontrol one or more elements (130) emitting light; characterized in that said apparatus it comprises unaparato width modulation pulse extended to transform a signal of (N + M) bits in a flujode 2M words width N bits for a total of 2M pulse cycles, the apparatus comprising demodulation width Extended pulse: c) means for receiving the signal (N + M) bits, d) means for dividing the signal (N + M) bits in a portion of N bits and a port...
Radiative flux transfer between Lambertian surfaces can be described in terms of linear resistive... more Radiative flux transfer between Lambertian surfaces can be described in terms of linear resistive networks with voltage sources. This thesis examines how these "radiative transfer networks" provide a physical interpretation for the eigenvalues and eigenvectors of form factor matrices. This leads to a novel approach to photorealistic image synthesis and radiative flux transfer analysis called eigenvector radiosity.
• here are two basic approaches to generating photorealistic images in computer graphics. The fir... more • here are two basic approaches to generating photorealistic images in computer graphics. The first approach involves ray tracing techniques; the second approach is radiosity. Radiosity is in some ways the complement of ray tracing. While ray tracing techniques excel in the rendition of point light sources, specular reflections and refl'action effects, radiosity meth~ ods accurately model area light sources, diffuse reflections, color bleeding effects and realistic shadows. Together, they offer rendering capabilities beyond those available from ray tracing or radiosity alone. The essence of ray tracing technique is the geometric ray. We model rays of light that emanate from the eye and propagate through the environment. We can create synthetic images by calculating their interaction (that is, reflection, refraction, absorption and so forth) with objects in the environment. In this sense, we can see that ray tracing models objects, or at least our perception of them, from a given viewpoint. Radiosity offers a fundamentally different approach. Given a complex environment , we can subdivide each surface into a mesh of polygons called patches. By modeling some of these patches as emitters, we can determine the inter-reflections, or multiple bounces, of light within the environment on a patch-by-patch basis. From these inter-reflections come the indirect lighting effects, gradations and soft shadows that can impart such a dramatic sense of realism to radiosity-based images. It has been argued that ray tracing offers view-dependent solutions, while those of radiosity are view-independent. That is, once the radiosity equation has been solved for a given environment , different views can be rendered very quickly. This, however, is a fallacy. Radiosity's view independence applies only to ideal diffuse (or Lambertian) surfaces. As Ward (1994) so eloquently reminded us, stochastic ray tracing techniques such as those used in RADIANCE are equally capable of view independence under these conditions. Radiosity is more than this, however. Whereas ray tracing models objects, radiosity models light. That is, radiosity models light as a five-dimensional scalar "photic field" that permeates any luminous environment (Moon and Spencer 198l). This field can be thought of as an infinite number of rays, each with its own measurable photometric brightness (or, more properly , luminance) at each point in space along its length. The objects in the environment become little more than the field's boundary conditions. Light as a five-dimensional scalar field? In terms of photorealistic images, this concept may have little to recommend it. …
The present invention provides an integrated independent lighting module, which may be used alone... more The present invention provides an integrated independent lighting module, which may be used alone or in combination with other modules, to produce white light of any other color within or chromatography. Each module includes one or more light emitting elements, and drive control systems, feedback systems, thermal management system, an optical system and a communication system can be optionally in communication between the modules and / or other control systems. Depending on the structure, the illumination module may operate autonomously, or may be based on an internal signal, or both signals or signal received from the outside to determine its function.
This is the story of a famous nineteenth-century commoner in the United Kingdom. His singular cla... more This is the story of a famous nineteenth-century commoner in the United Kingdom. His singular claim to fame was that he could "walk on water," a feat that drew tens of thousands of spectators at a time hopeful of a glimpse of him. Perhaps the most shocking indication of his fame was that in 1822, King George IV publicly bowed to him-a lowly commoner with no ties to royalty or the nobility-in acknowledgement of his capabilities. He was called "Mr. Kent, the Ingenious Inventor," a Scotsman from Glasgow. In literally hundreds of contemporary broadsheet and journal publications, it was simply assumed that the reader knew who he as. Beyond his name, however, history has recorded nothing about his background … or has it? Possibly the best approach to this question is to examine the chronological history of two men-"Mr. Kent" from Glasgow and William "Willie" Cant from Dunfermline, Fife, a small town just north of Edinburgh across the Firth of Forth.
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