Abstract: An apparatus for measuring a medical substance where a prism having a high refractive index, a thin metal film formed on one of the surfaces of the prism, a light source for making a light incident upon the thin metal film, and a detector for detecting an incident angle of a light being made incident upon a film on which a plasmon resonance phenomenon is generated on the thin metal film are provided. The medical substance, i.e. antigen as an object to be measured, is fixed to the surface of the thin metal film, and the condition for generating the plasmon resonance phenomenon is varied when a mixture of antibody which is coupled with the medical substance in a specific manner and a sample is made contact with a surface of the thin metal film; and the amount of the medical substance can be detected by recognizing the change with a high sensitivity.

Abstract: An X-ray analyzing apparatus according to the invention includes an excitation ray generator for applying an excitation ray onto a sample, and an X-ray detector which is sealed in a vacuum container along with a cooling device; a first X-ray passing layer, where a first gas exists, is provided in a path through which the characteristic X-ray generated from the sample travels to the X-ray detector; X-ray transmission windows are provided on the first X-ray passing layer and on the vacuum container so as that the characteristic X-ray can reach to the X-ray detector through the windows; the first and second X-ray transmission windows are separated from each other so as to provide a second X-ray passing layer therebetween; and the second X-ray passing layer is arranged to be a vacuum or a second gas is circulated through the second X-ray passing layer.

Abstract: An apparatus for measuring the Sulfur component contained in oil includes an X-ray tube having a target made of Titanium or Scandium, a filter made of Titanium or Scandium for filtering said X-ray radiated from the X-ray tube, a measurement cell for introducing a sample to be measured therein, and a detector for detecting fluorescent X-rays radiated from the sample. According to the invention, the X-ray tube has a target made of Titanium or Scandium and the X-rays generated from the X-ray tube are filtered by the filter, which is made of Titanium or Scandium, so that the background of the X-rays for the measurement against the fluorescent X-rays of the Sulfur is reduced and therefore even a small amount of Sulfur contained in the sample can be correctly detected.