Most microscopes, eye loupes, and optical comparators do not have the ability to provide lighting for the top surfaces of the specimen being viewed. If you want to examine a printed circuit board, you would have to use either ambient light or a hand held flashlight. This instructable will show you an easy way to light the top surface of your specimen. Most parts can be found in your junk box, but even if you bought all new parts, the cost would be less than $20 Interested? Lets get started!
Step 1: Materials you will need
You will need the following items:
1. A wall wart or wall transformer of about 6 VDC or more and rated at 50 MA or more.
2. A clothes pin or similar clamping device
3. Two or more white LEDs and several resistors of less than 500 ohms.
4. A two inch square of thin plywood, plastic, metal or other stiff but workable material.
5. Some solid or stranded wire of about 20 to 24 AWG
6. tape or shrink tubing to cover the wire joints.
7. A soldering iron and solder to solder the wires to the LEDs and wall wart.
8. Tools to cut and shape the plywood, wires, etc.
9. Drill bits or dremel cutter to drill holes for LEDs
There's nothing difficult or fancy here so feel free to improvise.
Step 2: Things to note before you start
The pictures show only my way of doing this. Feel free to improvise. You may want to add more or less LEDs or you may have an optical device with larger or smaller housings. Your dimensions and electrical requirements may be different from mine, so I have provided no drawings or schematics. It would be wise to layout your LEDs and wall wart before starting and check them for proper brightness or any overheating. Figure on about a 3 volt drop and 20 MA of current per LED. Do not connect the LEDs without proper current limiting resistors. Start with high values for the resistors. If you are not familiar with wiring LEDs, get some help or search the internet.