Evaluation Of Speckle Of Light-Diffusion-Fiber Using Laser Light Source

The speckle of the light diffusion fiber using the laser light source was evaluated. In displays, laser speckle is noise, and various ways to reduce it have been studied. On the other hand, for lighting, new applications can be expected that make use of the Attractivity-to-Eyes by the glare. In order to explore the possibility of a new fiber light source combining a laser light source and a light diffusion fiber, the state of speckle was measured. The degree of speckle is defined by speckle contrast (Cs) and is calculated by statistical processing of a measured image. The measurement of the fiber light source is difficult due to the fine line (small area), and we have proposed a unique measurement method. Furthermore, we have clarified that the speckle varies with the measurement angle depending on the fiber structure and the conditions of the optical scatterer. (C) 2020 The Japan Society of Applied Physics.