Rayotek Scientific, Inc. is a San Diego based company, founded in 1992 by a group of physicists and engineers with extensive experience in the semiconductor and nuclear industries. Rayotek was initially established as an R&D firm and over time has evolved into a full-service corporation.

Rayotek's mission is to provide its customers with a full-service facility that specializes in engineering -design and manufacture of precision sapphire, glass, fused quartz and fused silica products.

The experts at Rayotek are dedicated to providing creative solutions for the scientific and commercial industries. With a solid foundation of technical knowledge and creative experience, Rayotek has the ability to take customer's needs from the conceptual stage, through engineering-design, to final manufacture.


NPT Tapered Thread

NPT Sight Glass Windows

  •     NPT – ISO standard male tapered threaded sight glass
  •     Exhibits no outgassing or contamination of most systems*   
  •     Long working life
  •     No maintenance required
  •     Tested to high safety factor to insure safety & reliability
  •     Exceeds all industry and MIL standards
  •     Engineered, Manufactured and tested at the Rayotek U.S. facility 
  •     Ultra-High Pressure (UHP) tested to 20,000PSI or higher available

NPT Sight Windows, made to ISO 7-1:1994 standards, are a low cost solution for viewing and observation ports for fluid, flame and gas viewing, indicators and sensors. Rayotek NPT Sight Windows utilize glass, sapphire and other transparent materials sealed into a corrosion resistant metal housing to create a hermetically sealed unibody Sight Glass.

Rayotek NPT Sight Windows are exceptionally robust in extreme thermal, chemical, mechanical and pressure environments.  They also perform exceptionally in ultra-high vacuum, high purity, cleanroom rated systems.


  •     High pressure tanks
  •     Liquid level view ports
  •     Hydraulic level indicators
  •     Flame & explosion observation ports for furnace, heater & hazardous systems
  •     Supercritical & petroleum research systems
  •     All classes of refrigerant systems, including CO2-based R744
  •     Sanitary & FDA applications for pharmaceutical & food processing
  •     Simple lighting windows for deep sea, ultra high pressure & vacuum systems

Rayotek Sight Windows can reliably meet and exceed the requirements of many applications from industrial to research. The selection of window, housing material and sealing method will help optimize the best sight window configuration for your application.

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