NinjaPBR Light Source
The central parameter of the NinjaPBR is obviously the intensity of the provided light. Actinic light is provided using 5 cold white PLCC SMD LED Strips with rating 24V and 1.26W. The irradiation intensity is regulated using a pulse-width modulated signal from the Arduino. To ensure minimal irritation of the cells by the intermittent light regimen due to the resulting short light pulses, the PWM frequency is increased to 31.374 KHz and the resulting signal flanks are smoothed using a 1nF capacitor.
The resulting irradiation intensities are shown in the following figure, measured using a standard Licor Photometer with a planar sensor.
