Picture frame illuminated by LED A4 250x340mm double-sided for poster advertisement sign

The word LED, which is the acronym for Light Emitting Diode, is a passive optoelectronic component characterized by its versatility, taking on many forms and being integrated into many optical elements, from screens to light bulbs and even photographic flashes.

One of its best features is its low energy consumption, as well as its longer lifespan, its durability that perfectly withstands almost any type of vibration, in addition to low heat emission.

In the diagram:

1. Anode
2. Cathode

1. Lens/epoxy encapsulation (plastic capsule).
2. Metal contact (conducting wire).
3. Reflective cavity (reflective cup).
4. Semiconductor termination.
5. Anvil.
6. Post.
7. Anvil and post assembly replacing the filament.
8. Flat edge.

We can define the paper formats according to their measures and these are defined in ISO standard 216 one, which in turn includes the standard DIN 476. This applies in most of the world. I there are plenty of measures for the role, but the most used are the Serie A and to a lesser extent Serie B.

In Serie A, the most widely used format is the A4 (210x297mm) or also called "sheet" used in most printers and fotocopiadoras.

Series B is defined for intermediate sizes Series A. For example, the B4 is the intermediate size between A3 and A4.