Temperature measurement with photodiodes: Application to laser diode temperature monitoring

• Published in: Sensors and actuators. A. Physical. 2022-04, Vol.337, p.113441, Article 113441
• Main Authors: Földesy, Péter, Jánoki, Imre, Nagy, Ádám, Siket, Máté, Zarándy, Ákos
• Format: Article
• Language: English
• Subjects: Calibration; Diodes; Electrical measurement; Heat sinks; Laser diode; Lasers; Photodiode; Photodiodes; Photovoltaic cells; Semiconductor lasers; Sensors; Solid state lasers; Temperature control; Temperature measurement; Temporal resolution
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2022.113441

The temperature feedback of solid state laser diodes and various photovoltaic devices is critical for stable and reliable usage. We demonstrate that with a simple and passive electrical measurement process and optical calibration method the temperature of a photodiode can be determined, while keeping its original purpose. We present the idea with simulation and experiments, and provide an illumination-based parameter fitting method. The presented use case is a 5.6mm IR laser diode. We used its monitor photodiode to track the temperature inside the package with significantly better temporal resolution than the off-the-shelf external heat sink sensor provides. We reached a time resolution in the range of milliseconds and achieved precision of ±10mK with ±3K absolute, uncalibrated precision. The technique is not restricted to laser diodes, it is applicable to photovoltaic cells, photodiode arrays, organic diodes as well. The stability of atoms when they are released from confinement is studied. We consider H atom inside a spherical hard wall potential. The ionization probability is calculated for different initial confined states and radii. In the figure the probability density function for the ionization energy when the electron is ejected from the N shell confined to 6 au. The minima are close to zero the maximum is at the energy of the confined orbital. [Display omitted] •A TO can packaged laser diode temperature is measured by its monitoring photodiode.•Time resolution in the range of milliseconds and precision of ±10mK with ±3K absolute temperature achieved.•No complex instrumentation is needed, changing external illumination is used only for photodiode parameter identification.•Existing setups can be extended to monitor temperature with no additional sensors.•Other photosensitive devices can be monitored, such as photovoltaic cells, organic diodes, photo diode arrays.