Abstract: A photonic thermocycling device is configured to thermocycle a biological sample. The thermocycling device comprises a light source configured to emit an illumination beam, a reaction block holding a reaction chamber, and a light-absorbing film is coupled to the reaction block and configured to absorb and convert the illumination beam into thermal energy to heat the reaction chamber. A controller generates instructions for operation of the thermocycling device. The thermocycling device may further comprise a temperature sensor to measure the temperature of the reaction chamber for calibration of the instructions. A convection cooling element may also be implemented to provide rapid cooling of the reaction chamber. A lens assembly may be implemented for directing and conditioning light generated by the light source towards the light-absorbing film. A second partial light-absorbing film may be included and coupled on an opposite side of the first light-absorbing film, to improve heating uniformity.