Flashlight parts

From top to bottom, a flashlight is normally made of these parts: 1. Bezel2. Lens3. Reflector (or TIR)4. LED5. MCPCB (board the LED is soldered to)6. Metal heat sink (shelf or pill)7. Driver (makes the LED get the right current and voltage)8. Cell9. Tail cap 1-7 are contained within the head. Number 6 is where …

Measuring lumens without an integrating sphere or calibration source

Some people were asking how to measure lumens without much equipment. I’d recommend making a cheap integrating sphere (or tube) but you can get a rough idea of lumens with just a phone and desk lamp. Get the ceiling bounce app if you have an Android. Or search the app store for something like lux …