Photometric cell and probe having windows fusion sealed to a metallic body

A non-leaking photometric cell suitable for high temperature and/or high pressure industrial applications, comprising:

• a first window;
• a second window;
• a first metallic tube;
• a second metallic tube;
• a metallic body defining a cavity therein, the metallic body having at least a first aperture and a second aperture thereinto each in communication with the cavity, the first window positioned entirely in the cavity and near an end of the first metallic tube, the first metallic tube being positioned through and removably sealed to the first aperture, the second window positioned entirely in the cavity and near an end of the second metallic tube, the second metallic tube being positioned through and removably sealed to the second aperture;
• a first continuous brazed seal between the first metallic tube and the first window;
• and a second continuous brazed seal between the second metallic tube and the second window, so that light can be passed through the first window into a sample positioned between the two windows in the cavity and then through the second window to a photodetector essentially without any of the sample leaking between the first window and the metallic body or between the second window and the metallic body.