The GL Spectis 1.0 touch by GL Optic is an intuitively operated spectral measurement instrument with touchscreen for mobile light measurement. Offering the accurate determination of photometric and radiometric values, such as the color rendering index (CRI), correlated color temperature (CCT), color coordinates, radiant power or luminous flux, the instrument provides data significant in quality control or research processes. The device, originally developed for lighting designers or luminaire and LED manufacturers has now been optimized for the measurement of radiation relevant during plant growth.
Sunlight spans over a large spectral range, with wavelengths of 290 to around 3000 nm, thus from UV to near-infrared. The visible range for human eyes, as well as the radiation which is also used by plants for photosynthesis, is between 380 and 720 nm. This photosynthetically active radiation (PAR), made up of photons, constitutes about 40 - 50 percent of the emanated solar energy. At the same time, short-wave light such as blue is higher in energy than long-wave red light. In accordance with the chemical processes of photosynthesis, photons work effectively regardless of their energy content. Because of this, surplus energy is for example emitted to the leaves in the form of heat. Therefore, to determine plant growth it is necessary to measure the light quantity as photosynthetic photon flux density (PPFD), rather than the energy value of the absorbed radiation.
In addition to PAR, expressed in W/m², the specially developed GL SPECTIS 1.0 touch PAR/PPFD thus precisely measures PPFD values, expressed in µmol/m²/s, through the weighting of appearing wavelengths at varying magnitudes. Thus short-waved or more energy-rich wavelengths like blue are weighted at an appropriately lower magnitude than long-wave radiation. For scientists and biologists, values that can be measured using the GL SPECTIS 1.0 touch PAR/PPFD are of vital importance for the cultivation of plants and the research of plant growth. Even today, this light measurement instrument by GL Optic has already been implemented in a NASA project which is researching the cultivation of plants in outer space.
Measurements can be made using the small 74 x 124 x 26 mm instrument without a PC and saved on the supplied microSD card. In addition, the Android-based GL SPECTIS 1.0 touch features Wi-Fi connectivity and USB 2.0 for data transfer. For use in test setups, the measurement instrument features a screw adapter for installation on a tripod. Moreover, GL Optic offers an extensive range of accessories which includes integrating spheres, laboratory-grade software, as well as additional measuring instruments and individual solution concepts.