General-purpose bulb
A parameter that describes the brightness of the lamp compared to a general purpose lamp (LON — a conventional incandescent bulb). Simply put, an analogue of LON is the power of an incandescent lamp, which is equal in brightness to the model in question. For example, a
75W LON analogue means that the lamp glows as brightly as a 75W incandescent lamp.
This parameter appeared for the convenience of evaluating and comparing different types of lamps in terms of brightness. Data on the luminous flux say little to the average user, and it makes no sense at all to evaluate the brightness by power — different types and even different models of lamps of the same type can differ markedly in efficiency. On the other hand, many users are accustomed to dealing with incandescent lamps, and comparison with such a lamp is familiar and understandable to them. In addition, the LON analogue allows you to compare different types of lamps, and it can also be very convenient when replacing incandescent lamps with more economical ones: for example, if 100-watt lamps were used in the chandelier, then the new lamps must have an LON analogue of
at least 100 W — otherwise they may be too dim.
Scattering angle
The angle of light dispersion is the space in front of the light bulb, which is illuminated by the source itself, and not by the light reflected from the walls and interior items. In other words, the angle of light scattering determines the zone of the best illumination. Classic incandescent bulbs demonstrate the widest dispersion angle — they shine almost 360˚. LED spotlights have the smallest illumination angle, which are able to illuminate well only the area directly under the bulb — the scattering angle in such cases is about 15˚. Of course, a large angle of light scattering is not always needed. Working in the evening at the table, you need light only in front of you, so as not to disturb anyone. For spotlights that light up only small objects in front of them (a painting, sculpture, bas-relief, etc.), the scattering angle can even be from 4 °. As for the top (general) lighting, in this case it is better to choose something with a wider dispersion angle. These bulbs provide extremely uniform illumination.
Claimed running time
The service life of the light source claimed by the manufacturer is implied, during which the illuminator is able to generate the claimed brightness and temperature colour spectrum. It is believed that light-emitting diode (LED) bulbs have the longest service life — their working life can be 10,000 — 50,000 hours (
50 years of operation), depending on the modification of the bulb. But this parameter cannot be regarded as a guarantee, since
a lamp with an operating time of 25 years can work less, and maybe even more, than
a lamp with a "life" of 30 or even
35 years. In second place are energy-saving fluorescent light bulbs that are capable of generating daylight — the service life of such is in the range of 2000 — 20,000 hours. The average service life of halogen bulbs is about 2000 — 4000 hours, but when the power supply is equipped with a soft start device, it can be almost doubled. In last place are classic incandescent bulbs, the service life of which is within 1000 hours.
