Reaching <100  ppm/K output intensity temperature stability with single-color light-emitting diodes

Area of Science:

• Optics and Photonics
• Materials Science

Background:

• Stable optical sources are essential for metrology, medical devices, communications, and illumination.
• Existing methods often require complex temperature control or bulky components.

Purpose of the Study:

• To develop a simple, low-power optical stabilization scheme for LED output intensity.
• To achieve temperature coefficients below 100 ppm/K for LED output intensity.

Main Methods:

• Utilizes the peak-emission wavelength drift of an LED as a temperature feedback signal.
• Employs a weakly polarizing optical interference coating with polarization-dependent wavelength sensitivity.
• Implements a feedback loop using a weighted sum of two polarization outputs for power correction.

Main Results:

• Demonstrated an optical stabilization scheme for LEDs.
• Achieved output intensity temperature coefficients below 100 ppm/K.
• Eliminated the need for separate thermometers or temperature control stages.

Conclusions:

• The proposed method offers a simple and effective solution for stabilizing LED output intensity.
• The design is suitable for portable and battery-operated instruments due to its low power consumption and electronic calibration.
• This advancement benefits applications requiring precise and stable optical output.