Luminous flux provided by a lamp. This parameter is indicated only for models using built-in LED modules (see “Light source”) - in lamps with a socket, it will depend on the light bulbs used.
Luminous flux is essentially the brightness of the lamp. The brightness itself in lumens tells little to the average user, a non-specialist; however, there are tables that allow you to compare the luminous flux of a lamp with a particular light source of standard brightness. For example, a 40 W incandescent lamp produces about 415 lm, a 60 W lamp produces 710 lm, and a 100 W lamp produces 1340 lm. More detailed tables for comparison can be found in special sources.
Speaking of brightness, it is also worth noting that it should not be too low or too high: both create discomfort, increase fatigue and can lead to eye problems. Reference sources provide recommendations on optimal brightness for different tasks. However, this point can be determined for yourself experimentally. And if in doubt, you can purchase a lamp with adjustable brightness (see “Functions and capabilities”).
The colour temperature of the light emitted by the lamp. It is indicated only for models with built-in LED (see "Light source"), since bulbs with different characteristics can be installed in the socket. In luminaires with
colour temperature control(see "Features"), the minimum value is usually taken into account.
This parameter directly determines the hue of the visible colour. At the same time, its physical meaning is such that as the colour temperature rises, this shade becomes more
“cold”, shifts from yellow to blue. Here are some examples of colour temperature, for clarity:
— 1500 – 2000 K — candle flame;
— 2800 K — 100 W incandescent lamp (
warm light);
— 4000 K — a fluorescent
lamp of daylight white light(such light can already be perceived as cold);
— 5000 K — the light of the midday sun;
— 5500 K — a shade from white clouds at noon;
And so on, thickening to blue cold shades.
Note that the choice for this parameter depends not only on personal preferences and design considerations, but also on the general purpose of the lamp. So, a high colour temperature (from 5000 K) is considered optimal for reading, an average colour temperature (about 4000 – 5000 K) is comfortable for mathematical calculations, working with documents and other tasks that require concentration, and
...soft warm light up to 4000 K is good for relaxing and creating atmosphere of comfort.
