Search results for "red light"
showing 10 items of 55 documents
Determination of the object surface function by structured light: application to the study of spinal deformities.
1999
The projection of structured light is a technique frequently used to determine the surface shape of an object. In this paper, a new procedure is described that efficiently resolves the correspondence between the knots of the projected grid and those obtained on the object when the projection is made. The method is based on the use of three images of the projected grid. In two of them the grid is projected over a flat surface placed, respectively, before and behind the object; both images are used for calibration. In the third image the grid is projected over the object. It is not reliant on accurate determination of the camera and projector pair relative to the grid and object. Once the met…
Scanning from heating: 3D shape estimation of transparent objects from local surface heating.
2009
Today, with quality becoming increasingly important, each product requires three-dimensional in-line quality control. On the other hand, the 3D reconstruction of transparent objects is a very difficult problem in computer vision due to transparency and specularity of the surface. This paper proposes a new method, called Scanning From Heating (SFH), to determine the surface shape of transparent objects using laser surface heating and thermal imaging. Furthermore, the application to transparent glass is discussed and results on different surface shapes are presented.
Synthetic aperture superresolution by speckle pattern projection.
2009
We propose a method for increasing the resolution of an aperture limited optical system by illuminating the input with a speckle pattern. The high resolution of the projected speckle pattern demodulates the high frequencies of the sample and permits its passage through the system aperture. A decoding provides the superresolved image. The speckle pattern can be generated in a simple manner in contrast with other structured light superresolution methods. The method is demonstrated in microscopy test images.
Approche coopérative pour l'acquisition et l'observation de formes tridimensionnelles
2009
Technologic progres can reduce the barrier between real image and virtual image so far it is really difficult to recognize them. When virtual reality is well done, augmented reality, from virtual world to real world, is still developped. We want to project a virtual texture onto a 3D real object. By using cameras and projector, we estimate its real pose in the virtual reference by projecting a coded pattern to find points of correspondence between cameras and projector onto the textureless object, where common detector of points of correspondence are useless. We combine the calibration of the system and these points to estimate the 3D position of the object, and then register with a fine mo…
Multiple Structured Light-Based Depth Sensors for Human Motion Analysis: A Review
2012
Human motion analysis is an increasingly important active research domain with various applications in surveillance, human-machine interaction and human posture analysis. The recent developments in depth sensor technology, especially with the release of the Kinect device, have attracted significant attention to the question of how to take advantage of this technology in order to achieve accurate motion tracking and action detection in marker-less approaches. In this paper, we review the benefits and limitations deriving from the adoption of structured light-based depth sensors in human motion analysis applications. Surveying the relevant literature, we have identified in calibration, interf…
Robust technique for 3D shape reconstruction
2017
Abstract In this paper a robust and simple scheme is presented for three dimensional (3D) shape reconstruction of real object. A novel composite pattern technique is proposed for projecting the light pattern on the object of interest. The proposed scheme reduces the number of patterns by combining the primary color coded channels into one composite format. Our approach uses both spatial and temporal intensity variation for calibration and construction phase. Gamma calibration is considered with the propose scheme. High quality depth map is obtained from the linear light reflected by the shape of object without complex calculations. Experimental results demonstrated that proposed technique i…
Red-light-emitting electrochemical cell using a polypyridyl iridium(III) polymer.
2009
A deep-red phosphorescent ionic iridium(III) complex is prepared and incorporated into a polymer. Both the complex (1) and the polymer (2) were used as the single active material in solid-state light-emitting electrochemical cells (LECs). The devices built up using 1 and 2 emit in the deep-red region of the visible spectrum with CIE coordinates x = 0.710; y = 0.283 and x = 0.691; y = 0.289, respectively, making them one of the deepest-red emitting LECs reported. It is the first example of a polymeric LEC incorporating an ionic iridium complex, which exhibits increased stabilities compared with the device based on the small molecular weight complex.
Comparison of the Effects of Indole-3-Acetic Acid and Kinetin on the Photosynthetic Apparatus and on the Cell Metabolism
1984
External and internal factors can exert a regulatory influence on growth and differentiation within a reaction norm determined by the genetic material. As to the internal factors, the phytohormones intervene in the most development processes in a regulatory manner. In a number of publications it was pointed out that there is a far-reaching accordance between the effects caused by I.4A and the effects induced by red light and low light conditions (Zerbe, Wild, 1980 a; Holzapfel et al., 1982 a). Plants of Sinapis alba grown under low light conditions but additionally treated with kinetin show changes in their metabolism that are characteristic of plants grown at higher light intensities (Zerb…
The room temperature crystal structure of a bacterial phytochrome determined by serial femtosecond crystallography
2016
Scientific reports 6, 35279 (2016). doi:10.1038/srep35279
HIGH QUALITY TEXTURE MAPPING PROCESS AIMED AT THE OPTIMIZATION OF 3D STRUCTURED LIGHT MODELS
2019
Abstract. This article presents the evaluation of a pipeline to develop a high-quality texture mapping implementation which makes it possible to carry out a semantic high-quality 3D textured model. Due to geometric errors such as camera parameters or limited image resolution or varying environmental parameters, the calculation of a surface texture from 2D images could present several color errors. And, sometimes, it needs adjustments to the RGB or lightness information on a defined part of the texture. The texture mapping procedure is composed of mesh parameterization, mesh partitioning, mesh segmentation unwraps, UV map and projection of island, UV layout optimization, mesh packing and mes…