During the germination and growth of plant seeds, changes in the ratio of red light to far red light can lead to changes in spectral quality, thereby affecting the photosensitizing pigment Pr/Pfr status of plants. This has a direct impact on the photomorphogenesis of plants, which in turn affects their plant height, leaf diffusion rate, and other photobiological and botanical morphological responses.

The S2-442-SS visible light and far red light quantum sensor (PAR-FAR) adopts a dual channel design, which simultaneously measures and outputs the visible light (389nm~692nm) photosynthetic quantum flux density (PPFD) of the growth lamp and the far red light (700nm~750nm) quantum flux density. At the same time, the far red fraction is calculated to achieve quantitative monitoring of far red light quantum flux, reduce the need for more complex measurements using spectrometers, provide a more favorable light environment for crop growth, and make crop planting and cultivation more efficient.

S2-442-SS is a Modbus RS-232/RS-485 digital output, equipped with an M8 aviation plug, which simplifies the disassembly and replacement of sensors, facilitates maintenance and recalibration. It can also be directly connected to the AT-100 wireless Bluetooth data logger and controlled through mobile devices such as smartphones.