公开(公告)号：US5260584A

公开(公告)日：1993-11-09

申请号：US911501

申请日：1992-07-10

申请人： Stephen J. Popson ,  Kenneth A. Richey

发明人： Stephen J. Popson ,  Kenneth A. Richey

IPC分类号： G01J1/16 ,  G01N21/47 ,  G01N21/86

CPC分类号： G01N21/474 ,  G01J2001/1636 ,  G01N2021/4766 ,  G01N2021/8663 ,  G01N2201/06153 ,  G01N2201/0621

摘要： A portable, hand held reflectometer which employs at least one blue light emitting diode for measuring the optical brightness of an opaque material, such as a stack or pad of paper is disclosed. A brightness measuring reflectometer which employs two blue light emitting diodes arranged so as to substantially reduce measured brightness variations caused by changing the orientation of the reflectometer relative to that of the fibers contained in a fibrous material such as paper whose brightness is to be measured is also disclosed. An ultraviolet light source such as a fluorescent lamp is also employed for measuring the brightness of paper or other materials which contain ultraviolet light excitable blue wavelength emitting substances. An electronic circuit for operating the reflectometer is also disclosed which employs a negative feedback circuit for maintaining the intensity of the ultraviolet light source at a relatively constant level.

摘要翻译： 公开了一种便携式手持式反射计，其采用至少一个蓝色发光二极管来测量不透明材料（诸如纸堆或纸）的光学亮度。 使用两个蓝色发光二极管的亮度测量反射计，该蓝色发光二极管被布置成基本上减少由反射计相对于包含在诸如要测量其亮度的纸的纤维材料中的纤维的取向而引起的测量的亮度变化 披露 诸如荧光灯的紫外光源也用于测量含有紫外线可激发蓝色波长发射物质的纸张或其他材料的亮度。 还公开了一种用于操作反射计的电子电路，其采用负反馈电路以将紫外光源的强度保持在相对恒定的水平。