公开(公告)号：US4040747A

公开(公告)日：1977-08-09

申请号：US497727

申请日：1974-08-15

Applicant: Donald R. Webster

Inventor： Donald R. Webster

IPC: G01J1/18 ,  G01J3/12 ,  G01J3/28 ,  G01N21/31 ,  G01N21/35 ,  G01N33/10 ,  G01J3/48 ,  G01N21/48

CPC classification number: G01N21/314 ,  G01N21/3563 ,  G01N33/10 ,  G01J2001/182 ,  G01J2003/1243 ,  G01J2003/2866 ,  G01N2021/3129 ,  G01N2021/3159 ,  G01N2021/4769 ,  G01N21/35 ,  G01N21/4738 ,  G01N2201/1283 ,  Y10S250/91

Abstract: An automatic test instrument for gaging the percentage of various constituents in organic substances by comparing the reflective optical density of the subject at various wavelengths. Narrow band optical filters are connected together in the form of a rotatable paddle wheel positioned so that the filters can be individually swept through the incident light path between the specimen and wideband light source. As the filter wheel turns, the band of light passed by each filter is progressively shifted with the changing angle of the filter relative to the light path. The filter wheel configuration includes opaque vanes extending from the ends of the filters to periodically interrupt the passage of light to the specimen. Photocells are positioned to sense the level of light reflected from the specimen. The output of the photocells is sampled at pedetermined times relative to the rotation of the filter wheel to yield values indicative of reflected intensity at certain wavelengths. Using these values, an electronic circuit in one embodiment calculates three optical density difference values corresponding to moisture, protein and oil content of the specimen. The difference values are automatically inserted in three linear equations which are solved to obtain readings representing the true percentages of oil, water and protein contained in the specimen. Each time a new specimen is loaded for testing, the instrument is automatically calibrated against a standard sample, preferably Teflon (Trademark). The output of the photocells is amplified in a special circuit which subtracts the level of dark period current from the output when the photocells are illuminated.

Abstract translation: 一种自动测试仪器，用于通过比较不同波长的受试者的反射光密度来测量有机物质中各种成分的百分比。 窄带光学滤波器以可旋转的桨轮的形式连接在一起，其定位成使得滤光器可以被单独扫过样品和宽带光源之间的入射光路。 当滤光轮转动时，每个滤光片通过的光束随着滤光片相对于光路的变化角度逐渐变化。 过滤轮配置包括从过滤器的端部延伸的不透明的叶片，以周期性地中断通向样品的光。 光电池被定位以感测从样品反射的光的水平。 光电管的输出相对于滤光轮的旋转在规定时间被采样，以产生指示某些波长的反射强度的值。 使用这些值，一个实施例中的电子电路计算对应于样品的水分，蛋白质和油含量的三个光密度差值。 差值被自动插入三个线性方程中，这些线性方程被求解以获得表示样品中所含的油，水和蛋白质的真实百分比的读数。 每次加载新的样品进行测试时，仪器将自动根据标准样品进行校准，最好是Teflon（商标）。 光电管的输出在特殊电路中被放大，当光电管被照亮时，其从输出中减去暗周期电流的电平。