下载 Light Unit Converter 为 PC

1. It may be broadly defined to include all radiation with a wavelength between 0.1μm and 5.0μm or narrowly defined so as to include only radiation between 0.2μm and 3.0μm. There is little radiation flux (in terms of W/m²) to the Earth's surface below 0.2μm or above 3.0μm, although photon flux remains significant as far as 6.0μm, compared to shorter wavelength fluxes.

2. Photosynthetic Photon Flux - Photosynthetic Photon Flux (PPF), also known as Photosynthetic Photon Flux Density (PPFD) or Photosynthetically Active Radiation (PAR), designates the spectral range (wave band) of solar radiation from 400 to 700 nanometers that photosynthetic organisms are able to use in the process of photosynthesis.

3. Units include shortwave radiation (SW), photosynthetic photon flux (PPF, PPFD), Lux (lx) and Foot-candles (fc, lm/ft2, or ft-c).

4. Foot-candle - A foot-candle (sometimes foot candle; abbreviated fc, lm/ft2, or sometimes ft-c) is a non-SI unit of illuminance or light intensity widely used in the United States in photography, film, television, conservation lighting, greenhouse horticulture, the lighting industry, construction-related engineering and in building codes.

5. UV-C radiation spans from 0.1μm to .28μm, UV-B from 0.28μm to 0.315μm, UV-A from 0.315μm to 0.4μm, the visible spectrum from 0.4μm to 0.7μm, and NIR arguably from 0.7μm to 5.0μm, beyond which the infrared is thermal.

6. Alternatively, it can be defined as the illuminance on a one-square foot surface of which there is a uniformly distributed flux of one lumen.

7. PAR is normally quantified as µmol photons/m2/s, which is a measure of the photosynthetic photon flux (area) density, or PPFD.

8. The Light Unit Converter app from Apogee Instruments calculates the conversions between different light units for various light sources including T5 Sylvania fluorescent lights, metal halide, high pressure sodium, and sunlight.

9. Shortwave Radiation - Shortwave radiation (SW) is radiant energy with wavelengths in the visible (VIS), near-ultraviolet (UV), and near-infrared (NIR) spectra.

10. There is no standard cut-off for the near-infrared range; therefore, the shortwave radiation range is also variously defined.

11. The unit is defined as the amount of illumination the inside surface of a one-foot-radius sphere would be receiving if there were a uniform point source of one candela in the exact center of the sphere.