Related Experiment Video
Updated: Jun 17, 2026
08:44
Fabrication and Testing of Photonic Thermometers
Published on: October 24, 2018
Miniature optically immersed thermistor bolometer arrays.
1Barnes Engineering Company, Stamford,Connecticut, USA.
Applied Optics
|January 12, 2010
Summary
This study introduces novel five-element linear arrays of immersed thermistor bolometers for improved earth horizon detection. These advanced sensors utilize germanium and silicon optics for enhanced infrared atmospheric sensing in space applications.
Area of Science:
- Spacecraft attitude control
- Infrared (IR) sensing technology
- Atmospheric remote sensing
Background:
- Immersed thermistor bolometers have been utilized since 1958 for IR horizon scanners in spacecraft attitude control.
- Current detectors typically use a single thermistor flake immersed in germanium or silicon optics.
- Earth's atmospheric horizon studies highlight key IR spectral bands (CO2 near 15µm, water bands >20µm) for effective detection.
Purpose of the Study:
- To describe two novel types of five-element linear arrays of thermistor bolometers.
- These arrays are designed for an advanced horizon definition study program.
- To optimize infrared detection for specific atmospheric constituents.
Main Methods:
- Development of five-element linear arrays of thermistor flakes.
- Optical immersion of thermistor flakes in germanium and silicon lenses.
- Utilizing germanium immersion for the 14-16µm (CO2) spectrum and silicon for the >20µm (water) spectrum.
Main Results:
- The described detectors offer enhanced capabilities for horizon definition.
- Germanium-immersed detectors show optimal performance in the carbon dioxide spectrum.
- Silicon-immersed detectors are best suited for detecting atmospheric moisture beyond 20µm.
Conclusions:
- The developed linear arrays of immersed thermistor bolometers represent an advancement in IR horizon sensing.
- The choice of immersion material (germanium or silicon) is critical for targeting specific atmospheric spectral bands.
- These sensors are crucial for advanced attitude control and atmospheric studies of Earth from orbit.
Related Concept Videos
01:43Thermosensation
Peripheral thermosensation is the perception of external temperature. A change in temperature (on the surface of the skin and other tissues) is detected by a family of temperature-sensitive ion channels called Transient Receptor Potential, or TRP, receptors. These receptors are located on free nerve endings. Those detecting cold temperatures are closer to the surface of the skin than the nerve endings detecting warmth. These thermoTRP channels, while temperature selective, have relatively...
01:22Thermometers and Temperature Scales
Any physical property that depends consistently and reproducibly on temperature can be used as the basis of a thermometer. For example, volume increases with temperature for most substances. This property is the basis for the common alcohol thermometer and the original mercury thermometers. Other properties used to measure temperature include electrical resistance, color, and the emission of infrared radiation.
As many physical properties depend on temperature, the variety of thermometers is...
As many physical properties depend on temperature, the variety of thermometers is...
01:13Equipments Used to Measure Body Temperature
Body temperature can be assessed using various devices and measured in Celsius or Fahrenheit.
Glass-bulb Thermometer:
Glass-bulb thermometers are hollow glass tubes with a bulb tip containing liquid such as ethanol or mercury. Historically, glass bulb mercury thermometers were the standard device to measure body temperature. Today, mercury thermometers are prohibited in many countries due to the hazardous effects of mercury and the risk of exposure if the glass bulb breaks. In general,...
Glass-bulb Thermometer:
Glass-bulb thermometers are hollow glass tubes with a bulb tip containing liquid such as ethanol or mercury. Historically, glass bulb mercury thermometers were the standard device to measure body temperature. Today, mercury thermometers are prohibited in many countries due to the hazardous effects of mercury and the risk of exposure if the glass bulb breaks. In general,...
01:14Temperature Measurement Sites
A thermometer measures body temperature. The common sites for measuring body temperature are the oral cavity, axillary region, temporal artery, and skin surface, such as the forehead, abdomen, and axilla. True core body temperature is assessed in the rectum, tympanic membrane, pulmonary artery, esophagus, and urinary bladder.
Oral: When assessing oral temperature, the thermometer tip should be placed under the tongue in the posterior sublingual pocket. It offers accurate readings and can be...
Oral: When assessing oral temperature, the thermometer tip should be placed under the tongue in the posterior sublingual pocket. It offers accurate readings and can be...