Abstract: A high-precision spectrum separation apparatus enables to generate an output beam having a specific wavelength from a multi-wavelength input beam. The input beam is focused on a diffraction grating through a focusing lens to generate a number of diffracted component beams, of which a diffracted component beam having a specific wavelength is directed to an output slit, resulting in an output beam having well-defined spectral properties. When the output beam is required to have a band of wavelengths, the fixed focal distance of the focusing lens is shorter than is required to generate well-defined output beam, resulting that the diffracted component beam cannot be focused precisely on the output slit. In such a case, a flat glass plate is introduced between the focusing lens and the output slit to adjust the focal-point of the focusing lens so that the diffracted component beams are focused precisely on the output slit. An output beam having well-defined spectral properties is thus produced from the apparatus.

Abstract: A tubular furnace having an inner body connecting by an integral radially extending web. The web is positioned on the side of the tubular furnace so that a sample placed in the inner body and resting in the bottom thereof will not be heated by the web. Other embodiments illustrate the web positioned at different axial locations.

Abstract: A spectroscope device of the dispersion type receives light to be measured and emits it as dispersed light which corresponds to each of wavelengths to be measured. An optical-path switching device directs the dispersed light emitted from the spectroscope device to pass through first and second paths. A first photoelectric converter receives the light which is directed to pass through the first path by the optical-path switching device. A polarizing/separating device polarizes and separates the light, which is directed to pass through the second path by the optical-path switching device, into two polarized lights. Second and third photoelectric converters respectively receive the two polarized lights divided by the polarizing/separating device.

Abstract: A demand modulated electrothermal atomization plasma spectroscopy system intended to reliably and controllably atomize samples. The invention is used in conjunction with a plasma spectroscopic instrument, and includes a feedback control loop that monitors the rate of analyte consumption in a plasma torch and regulates the temperature of an electrothermal atomization means that supplies analyte material to the plasma torch. The feedback system in the preferred embodiment regulates atomization temperature based upon ion or photon count rates.