Light ring for mounting on webcameras

The main purpose of a light ring is give a smooth and well defined
illumination for the objects you are capturing. By having the light
come control from a circle around the camera you can make sure that no
visible shadows are cast (from the point of view of the camera).

What you need

To print:

• front.stl
• back.stl
• diffuser.stl (white or semi-transparent plastic)

Consumables:

• 9 x 5mm LEDs (white)
• Power-source: 25 - 30V, <0.1A

Tools:

• Pliers
• No soldering needed

How to use

Start by printing the "front" part. Attach 9 x 5mm LED's (preferably
white) by sticking their legs in through the small holes, with the LED
facing the flat side of the ring. Make sure to place all the LED's in
the same direction, eg. let the anode (long leg) always be on the
clockwise side.

Pull out the two closest legs from two diodes on the side with opening
that don't have a diod just below it. Connect all the diods together loosly
by wrapping their legs together so they form a chain around the
light-ring.

(IMPORTANT) Make sure that only connect long-legs to short-legs, never
two legs of the same length to each other.

Try attaching the power source to the light ring. The positive voltage
(+) should go to the long leg that is sticking out and negative
voltage (-) to the short leg. Note that if you don't use white leds
then the total voltage should be lower.

If the ring is not lighted up right now you either have missed to
connect some of the legs or have connected some in the opposite
order. It could also be that you have a too weak powersource or that
you have burned up one of the LEDs.

Once the ring is shining ok you can tighten the connection between the
legs using the pliers. Cut away the part sticking out and push the
remainder down so it fits snugly.

Finally, attach the back-side that you printed by pushing it in when
aligned to the two holes, and then rotating 90 degrees. It should stay
attached, if not then you may need to push down some leg that is still
in the way.

The diffuser goes on-top of the LED's and is used to diffuse the light
so avoid sharp glares. Make sure you print it in a light coloured or
semi-transparent plastic. White PETG works well for me.

How to modify

You can change the parameters of the object by opening the file
light_ring.scad using the program "OpenSCAD" that can be downloaded
from the internet.

http://www.openscad.org/

Go to one of the lines containing the parameters:

inner_r = 30/2; //< Radius of hole for cameraouter_r = inner_r + 10; //< Outer radius of center partpin_r = 1; //< Thickness of LED legs. Increase if holes are too smallpins = 9; //< Number of LEDs

Select which part to render at a time by commenting out all but one of
the parts:

/* Diffuser */translate([0,0,-30])diffuser();/* Front */front();/* Back */translate([0,0,30])rotate(180,[1,0,0])back();

Next, press F6 to render it and use "File > Export > Export STL" to
export your STL file.