Beginner’s Guide to explain simple LED flashlight

Here is a “Beginner’s Guide” to explain simple LED flashlight concepts.

To show how it works.

1. Reflector or Lens – used to control beam pattern, change angle of projection.

The reflector profile is the most important aspect in if the beam tightly focussed or spread out to give flood light. Deep reflectors typically create a tight spot and shallower reflectors a flood beam. The reflector surface finish then goes towards smoothing out the beam (using a textured surface) or reducing losses (with a mirror finish) but potentially having artefacts in the beam.

2. LED – Light-emitting diode, the modern Led is much brighter than Incan bulb and life span is much longer too. The efficiency or brightness of Led will be improved ~30% every year.

3. Heatsink – Cooling is required to remove the waste heat produced by Led. Consequent heating according to workload.

Brighter = Hotter. Nowaday the metal body of flashlight use as heatsink.

easy explanation asked for aluminium/Copper/silver, pls

4. Electronic Driver – control the power and signal to led.

The driver play a very important role here, because the led need ~3-4V only, but the battery capacity will drop according to life.

The driver can control the brightness by varing by current (or PWM)

eg. 1.5V AA battery boost driver (step-up) to ~3V to Led. or 2x Li-ion 8.4V battery buck driver (Step-down) to ~3V to Led.

eg. 3 diffenent power level – High, middle, low.

5. Battery – AA, AAA, CR123, Li-ion 18650 …….

6. Switch – Control On and OFF, change power level

Forward Clicky:

– light comes on before it clicks

– momentary on (when the light is OFF you can half press the switch to flash the light ON)

– you cannot use the switch to change mode (in certain multi-mode lights) without completely turning off the light

Reverse Clicky:

– light come on after it clicks

– momentary off (when the light is ON you can half press the switch to momentarily turn the light OFF)

– you can use the switch to change modes (in certain multi-mode lights) while the light is turned on


– Turn the of head or tailcap, like MiniMag

Leave a Reply

Your email address will not be published. Required fields are marked *