This cute badge is approx. 45 mm (1.77 in) and is designed around the simple add-on (SAO) design. This was a simple project where I experimented with different LED layouts to see how the light would diffuse and distribute through the PCB board from the backside. Two small batches were designed and printed for both Bottom View LEDs and Side View LEDs.

Bottom View PCB

The areas around the ears and horn, on the front side, are void of silkscreen, solider mask, and copper to expose the fiber board. Whereas, these same areas, on the back side, only have a round void opening for the size of the LED. This allowed the light to diffuse through the board. While this worked, I was not as pleased with how the light was distributed around the entire front side area for the ears and horn.

Also, for the Bottom View LEDs, I used Top View LEDs installed upside down. I used these due to availability and cost. While they did work, it was a challenge to solider them onto the board. I pre-tinned both the LED and PCB pad and then used a good size solider drop on the tip of the soldiering iron to connect the LEDs to the pad. The connectors on the Top View LEDs come down about halfway on their side, so this helped to connect them to the pad.

Side View PCB

The areas around the ears and horn, on both the front and back sides, are void of silkscreen, solider mask, and copper to expose the fiber board. This allowed the light to diffuse and distribute through the board. While the distribution of light was better, than the Bottom View LEDs, it was not as distributed as I would have liked. After some researching, I came across @TwinkleTwinkie who had the same issue from previous projects. Thanks to @TwinkleTwinkie I took an additional step and experimented with using hot glue to cover the Side View LED and areas on the back side to see if this would help distribute the light more evenly. Not only did this help with distribution, but it also allowed the light to be more intense through the board.

Important: Due to a bug in the side view led component of the schematic, the negative and positive labels for the LEDs are reversed. When you solider the LED, make sure the Anode (+) is connected to the negative labeled pad. You can use a multimeter on continuity test to verify the traces (routes).