Development of Portable Spectrometer supporting, Automatic Control of Integration Time
*Corresponding Author E-mail: email@example.com
Spectrometer is a device that can measure the intensity of light by wavelength. Though it is necessary to set an adequate integration time to measure the lighting environment, it would be difficult for general users to adjust time setting.
In this paper, we propose a portable spectrometer realizing an automated integration time and consequent automation of eliminating dark current to improve convenience of measurement. The proposed portable spectrometer is constructed with a light source measurement module, integration time automatic control module, dark current automatic elimination module, and communication module. The light source measurement module is developed using a small-sized spectral sensor, and miniature and mobile convenience could be obtained by implementing Bluetooth based remote control function. Furthermore, integration time automatic control module and dark current elimination module were implemented to improve measurement performance of the spectrometer.
Measurement performance of the spectrometer is associated with integration time control and consequent elimination of dark current. Integration time should be appropriately controlled according to the amount of light, while dark current is a noise generated in proportion to the integration time, which should be eliminated. The proposed portable spectrometer measures a time taken for the amount light collected through the spectral sensor reaches to the target saturation. The measured time was therefore set as the automated integration time and intensity of the illumination light was measured, and then module for automatic removal of the dark current was developed and implemented. The obtained values were corrected and analyzed using a mercury lamp and standard light source A. The average of absolute errors of indicated wavelength was around 0.415 nm, while the average of error for spectral irradiance was around 0.35%, complying the performance requirement of spectrometer specified in Korean Industrial Standards (KS).
Portable spectrometer has been developed that can be easily used by general users by implementing automatic integration time control and consequent dark current automatic elimination module.
Spectrometer, Integration Time, Dark Current, Measuring Lighting, Automatic control.