What LEDs are used for flashlights

To understand what the best LED for a flashlight, you need to familiarize yourself with the varieties of this element. If you need to illuminate dark rooms or the street, you can opt for a bright flashlight with LEDs of white glow. This will be enough to see the road in front of you for about 15-20 meters.

When it comes to a portable light, which should cope with more complex tasks, you need to pay attention to the performance of the luminous flux. For example, an expensive and powerful flashlight will be able to illuminate a large space due to the amplified beam.

Types of flashlights with LEDs

There are several varieties of flashlights that use LEDs, namely:

• In the form of a keychain. This is a miniature product for illuminating objects that are at a distance of 1-2 meters or closer;
• universal. Comes in handy on the street, where there is no lighting, as well as in the home. The lantern is compact and lies comfortably in the hand. Often has a metal or plastic housing. Optimal value of luminous flux for this variety is 30 Lumens;
• tactical. Purchased by hunters, rescuers, military and other special services. These devices are distinguished by their reliability, advanced functionality and power. The light output can exceed 300 Lumens;
• Tourist. The product is characterized by increased power, the ability to adjust the angle of the light beam and multi-functionality. Most models are equipped with additional accessories, such as a signaling device;
• lamp. Suitable for lighting the camping spot in a camping trip or tent;
• underwater. Used by divers and is waterproof;
• searchlight. Flashlight designed to be carried in the hand. Features increased brightness and range of illumination (up to 300 meters). It has a compartment for batteries.

Fig.1 - types of flashlights.

Speaking of LEDs, depending on the type of flashlight, they are equipped with SMD chips, LED or super-bright five-millimeter diodes for signal-type flashlights. It is the latter chips that used to equip almost all LED flashlights.

Fig.2 is a 5 mm super-bright diode.

Their main advantage is low power consumption and compactness. The first high-power flashlights were equipped with several signal diodes mounted on the same plane. Each of them had its own reflector, which directed the luminous flux to the same point as the others. This design is still used today for searchlights.

Types of LEDs in flashlights

Every year on the market there are more and more flashlights with improved LEDs. The most popular and quality are considered chips from Cree inc. such as XR-E, XP-E, XP-G, XM-L. In addition, the latest models of LEDs XP-E2, XP-G2, XM-L2 are in demand, they can be found in flashlights of medium and small size.

LEDs from Cree, which are often used in flashlights, are divided into several groups according to color temperature, viz:

• Group 1-2 - cold light (5250K);
• 3-5 group - neutral (3700-5250);
• Group 6-8 - warm (below 3750K).

Fig.3 - types of chips for flashlight.

Speaking of LEDs MT-G2 and MK-R from the company Luminus, they are installed in large searchlights, working on 2 batteries.

LEDs are also divided by brightness. This parameter is determined by using a special code. Choosing LEDs, it is worth considering their dimensions, as well as the area of light-insulating crystals. If it is small, it indicates that the flashlight shines far away, when the beam is concentrated in one point. To get a wide scattered light will need a large reflector, which will affect the size and weight of the product.

Which LED is the brightest and most powerful for the flashlight

Trying to pick up a LED flashlight with increased brightness characteristics, it is worth knowing that such parameters do not provide a high range. However, an increase in these characteristics will have a positive effect on the indicator.

Fig.4 - design of the brightest LED.

The main role is always played by the LED in conjunction with the optics. A device with a 500 Lumen rating sometimes shines farther than a flashlight with 5000 Lm. If you need the brightest and at the same time the longest range flashlight, you should focus on devices that are based on the XHP70 LED, which produces 6000 Lumens.

Choice of LEDs for the flashlight

Choosing a diode for a flashlight, you should consider the following:

• optical system;
• luminous intensity;
• purpose;
• design features. This refers to protection against mechanical damage, dust, moisture, as well as the way of holding the device in your hand;
• the power of the lamps;
• battery capacity;
• color temperature;
• optical system.

To assemble a powerful flashlight, it is recommended to install LEDs from the company Cree from the XM-L and XM-L2 line. In the floodlight models it is better to buy chips from MKR and MT-G2 series. For the brightest flashlight buy Luminus SST diodes.

Fig.5 - diode from Luminus SST series.

You also need to consider the angle of illumination. XR, XM and XP series LEDs have an angle of 90 to 120°, and the luminous flux will be 280 Lm. The power of the device in this case will not exceed 2 W. Since the most powerful product requires a current of up to 13000 mA, its value can reach 40 watts. Several varieties of batteries are sometimes installed in the flashlight, viz:

• Lithium-polymer;
• lithium-ion;
• nickel-cadmium;
• Nickel-ion.

If it is a pocket flashlight, ordinary finger batteries will do. In professional models, a battery is installed. The best option is considered to be lithium-ion, which have more power in a compact size, as well as a high heat output. Their only disadvantage is the rapid discharge at low temperatures.

Replacing the LEDs in the flashlight

When you have managed to understand the choice of LED, you can start the process of replacing it. Flashlights in most cases differ only in the number of diodes and the type of housing, so the replacement is performed on the same principle. For the work you should prepare the following:

• tweezers;
• multimeter;
• soldering iron;
• screwdriver;
• flux and solder.

Note that you may need additional materials and tools in the process. First you need to disassemble the flashlight. The first step is to remove the power sources (batteries or rechargeable batteries). If it is a pocket or searchlight, most likely the battery compartment is behind the cover.

Next, you can proceed to removing the protective glass. To do this, you need to unscrew the front cover. The glass is sometimes removed separately or attached to the cover itself. Then the reflector is removed. It must simply be removed or unscrewed.

Fig.6 - lantern in disassembled form.

The next step is to remove the diodes. Sometimes they are combined with the reflector. In this case it is easy enough to disconnect them, because the board is connected with small screws to the reflector. If it is a more expensive flashlight, you will have to disassemble it with an Allen wrench. The contacts are unsoldered with a soldering iron, and the LED is carefully removed with tweezers.

Tips to watch video: Replacing LEDs in a flashlight.

Before buying a LED for replacement, it is worth considering that the substrate must match the configuration and dimensions of the element to be removed. Otherwise, the master will have to make slits for the wires. Do not forget about the purpose of the flashlight. So, for scattered light or to increase the range characteristics, different models of diodes are suitable.