What is the meaning of PPF, PPFD, lumen and color temperature of LED plant lamp?

Gong believes that many new friends, contact with plant lights, or LED lighting, will hear some industry terms, such as :PPF, PPFD, lumen, color temperature and so on, what are the specific meaning of these words?
Today xiaobian sorted out this easy to understand terminology for everyone, let's have a look.

PPF: Photosynthetic Photon Flux refers to the number of micromoles (umol/s) of photons emitted per second by artificial light source with a wavelength of 400-700nm. Simply put, it's how many light and photons a lamp can emit per second.

PPFD: Photosynthetic Photon Flux Density, which can be considered as PPF within one square meter (unit: umol/m2s), is the concept of Density. In simple terms, in plant lamp applications, the total number of photons per second hitting the plant in a unit range is inversely proportional to the irradiation distance.

Lumen: A physical unit (lumen, lm) that describes the flux of light. Simply put, it is the brightness of a light bulb. The actual effect of bulb lighting depends on the size of the room, the color of the walls, the placement of lights and other factors.

Wattage: Also known as power, is the amount of energy consumed by a lamp, usually measured in watts (W). If you have switched to LEDS, focus more on lumens than wattage. (Incandescent bulbs consume more energy than popular LED bulbs. A 60-watt bulb emits far less light than a 60-watt LED bulb, and replacing a 60-watt bulb requires only an 8W or 12W LED bulb to obtain roughly the same number of lumens.)

Color temperature: A measure of the color content of a light, measured in K, KelvinScale. Simply put, it is the color or tone of the light. Generally in the field of plant lamp common white 3000K, 5000K, red 660, blue 460, which is often heard: warm white light, positive white light, neutral light, natural light, cold white light, pink light and so on.

2700K is a typical incandescent light color;

3000K to 4000K is warm white or yellow white, giving a warm feeling;

4000K to 5000K bright white, soft and vibrant (many eye protection lamp color temperature is between this);

5000K to 6500K is close to the sunlight color, the tone is bluish (summer noon sunlight 5500K)...

Color temperature is higher, tonal slant cold blue, give the vision with cool feeling.

Finally, a color temperature control map for your reference: