Abstract: A method and apparatus is disclosed for use in performing automated classification of cells and other microscopic specimens. The apparatus provides a compact, adjustable assembly that is operable to provide: an operator-apparatus interactive classification system for the cell analysis; alternative techniques for different cells, cytoplasms and cell populations; and enchanced image or color separation and analysis.

Abstract: A method and apparatus is disclosed for use in performing automated classification of cells and other microscopic specimens. The apparatus provides a compact, adjustable assembly that is operable to provide: an operator-apparatus interactive classification system for the cell analysis; alternative techniques for different cells, cytoplasms and cell populations; and enhanced image or color separation and analysis.

Abstract: A method of calibrating reflectance measuring devices, such as spectrophotometers, that incorporate automatic gain or sensitivity setting capability. According to the method, offset reflectance and reflectance of a secondary reflectance standard for several wavelengths are calculated and stored in a memory of a reflectance measuring device. A secondary standard is mounted in the reflectance measuring device and reflectances at a selected wavelengths from the secondary standard are read prior to measurement of the reflectance of the test sample. The stored offset reflectance and secondary reflectance for the operational wavelength are used to calculate true reflectance of the test sample.

Abstract: Reflectance standards are prepared in accordance with the present invention by incorporating at least 40 percent by weight of barium sulphate into acrylate polymer such as methyl acrylate or methyl methacrylate. Thickness of the resulting polymer should be in excess of 0.25 centimeters. By incorporating varying percentages of carbon black in the mixture during mixing--various reflectance values can be obtained. The resulting reflectance standards can be utilized in the form of chips, plaques, sheets, or can be molded into various configurations, including that of an integrating sphere.

Abstract: A readhead with reduced height sensitivity for use in a reflectance photometer that measures reflectance of diffuse light from a sample disposed outside the readhead includes a housing with an upper spherical portion and a lower conical portion. The inner peripheral surface of the upper portion is hemispherically configured and the inner peripheral surface of the lower portion is conically configured to permit illumination of a sample disposed outside the readhead. The angle of the cone defined in the conical portion of the housing is in the range of 45.degree.-60.degree.. The inner peripheral surfaces of the upper and lower portions are coated with a highly reflective material, such as barium sulfate. The apex of the conically configured housing portion is truncated to provide a light transmitting aperture for sample illumination. A sample is positioned adjacent the light-transmitting aperture below and outside the conically shaped readhead housing portion.