Ocean Optics has released an add-on module for its SpectraSuite spectrometer operating software. The add-on allows users of the company's miniature spectrometers and Jaz optical sensing systems to calculate Photosynthetically Active Radiation (PAR), an important parameter for evaluating the effect of light on plant growth. SpectraSuite-PAR uses the absolute irradiance spectrum (captured by the spectrometer) of the light incident on plants and other samples and converts the irradiance values from µW/cm2 (microwatts per square centimetre) to µmol/m2/s (micromoles per square meter per second), the measurement unit more commonly used for PAR analysis.

In addition to calculating total PAR, SpectraSuite-PAR allows users to define up to five 'wavelength bins' (the range of wavelengths to be covered in each data bin), which can be correlated to different phases of plant growth. For example, a bin can be configured over the 400-480nm range to capture the effects of the blue region of the spectrum, which is typically associated with early stages of plant growth. Also, customers can calculate both the percentage of light in each bin and the red/far red ratio, a parameter associated with plant development and structure.

SpectraSuite-PAR is a particularly powerful analytical tool when used as part of a field-portable Jaz sensing system configured for horticultural applications. Jaz is a family of modular, stackable components. At its heart is a miniature CCD-array spectrometer, or light measuring device, available with user-selected grating and slit options optimised for a variety of optical sensing application needs. SpectraSuite is the standard operating software for Ocean Optics spectrometers.