Inside of LED Light Bulb

What is inside a set of led lights? By opening a play of light of the trade, we discover the LED matrices, e-cards, but no engine and no fan.

Inside of LED Light Bulb

General view of the open play of light LED

There are 4 matrices 64 LED 5 mm square. There are 4 LED colors: red, green, blue and white cold.

LED light set (and cat electronics)

The principle is simple: focus the image of the LEDs using a converging lens (in fact, a magnifying glass). The focal length is typically 20cm.

Optical principle of the LED light set

Dynamics and “movements” of the light effect

There is no engine that allows the rotation of mirrors. The dynamics is linked to a sequence of ignitions and extinctions of programmed LED early in the play of light, like pixels screen in all or nothing. 4 matrices are independent.

The play of light LED matrix

LED matrix of light (disconnected from the play of light for the photo)

Rear view of the play of light LED matrix

There is no refroidissemnt (plan of dissipation by tracks). It comes to 20mA LED high efficiency which almost do not heat. They warmed when they are on because they are close to each other.

Detailed view of the LED

We notice that the white LEDs have a characteristic yellow light a fluorescent powder carpeted background. A white LED is a blue LED with a fluorescent powder that radiates in the area from yellow to red.

The manufacturer has chosen a repetitive Organization for the colors of the LED. The play of light is more ordered than fanciful.

Play of light LED mode “Spotlight”

Lit LED matrix

Rendering of the LED light set

Rendering of the ground LED light set

Rendering of the play of light LED: projection over a distance of 3 metres

On, there are 4 images that are the same field because of the parallelism of the lenses. With a smoke machine, the effect takes all its spatiality, which can evoke a game of LASER light.

Rendering of a set of LED light with smoke (not the one studied here) machine

Cards of the LED light set

On the map of the LED matrix, we see LED drivers. A small heater stuck on it ability to know which component it is…

The play of light LED driver

A current through a resistance measurement series 2.0 Ohm (2 x 1.0 Ohm in series). When all LEDs are on, measure 295mV to the terminals of each 1.0 Ohm resistance. There are so 295mA distributed over 16 LED (there are 16LED of each color and 4 sets of 2 resistors in series). The current in each LED is 18.4mA (= 295mA/16). It’s LED 20mA standard.

Resistance series, “sense”, to create a picture of the LED current voltage

A DMX card is also fixed in front back light.

Map light LED DMX

The play of light can also be controlled by music (built-in microphone).

Intelligence is centralized in this chip:

Intelligence of the LED light set

On this map, there is a power supply 5V to 12V (observe 100uH square inductance “101” on the left) for feed op amp and a linear regulator 7805.

A 230V to continuous 5V switching power supply feeds the whole game of light. It measures 5.03VDC in operation. No mechanical protection prevents someone from touch when the play of light is open. Be careful! About 5W to 10W consumption takes place.

Switching power supply 230V to 5V for the LED light set

Conclusion on the LED light set

It is a play of light LED to 300 euros, which has no engine or fan. It allows a very long life expectancy and total silence. This light full game of rotating lamps or the LASER effects creating intermediary effects between the two.