How to isolate light for a backlit silicone switch keyboard?

Backlit silicone switch keyboard also called as backlit silicone keyboard.

For a backlit silicone switch keyboard, how to isolate light and prevent it from transferring from one button to another button is very important.There are several solutions.

1.Insert molding light block.It blocks the light from being able to transfer from one light source to another through the silicone switch keyboard.

When a silicone switch keyboard need different color LED to illuminate the surface laser etched indicators, the light block not only can prevent light from bleeding into other portions of the switch keyboard but also focus the light source to indicate the indicators.

Silicone switch keyboard with light block are producing by insert molding or overmolding .Firstly, mold the light blocks in a separate mold.In a second shot, the light block is placed in the final mold and silicone is wrapped around the light block to create the switch keyboard.

The insert molding process gives you peace of mind by not having to worry about leaking light and light bleeding.

**The light blocks can be soft elastomer silicone rubber or hard plastic.Generally, if choose rubber light blocks, the hardness should be more than 60A.

2. Silicone or plastic grid.Design and produce a grid to match with the switch keyboard, which can effectively prevents light from passing through the bottom of the switch keyboard.

It have to pay attention to the tolerance and the clearance between buttons and grid.The clearance should be as bigger as possible.Xiamen Better Silicone Rubber Co.,ltd has produced a big silicone switch keyboard.The keyboard is big and with many buttons.In order to isolate the light from each LEDS, customer designs a silicone grid, which fit and match the keyboard by secondary assembly.For such a large product, the size deviation will be large and easily cause misplacement after assembly.So we increase the clearance from 0.2mm to 0.5mm.

**If choose silicone grid, the hardness is suggested to do higher, more than 60A.

3. Backlit silicone switch keyboard by spraying and laser etched characters.

This is the most traditional way.The silicone switch keyboards are molded in clear silicone first.Raw silicone without pigments will appear transparent (clear) or slightly milky white after molding.Then sprayed with the desired coating and laser etch the layers to create the characters and symbols.Only the characters and symbols are backlit.

Choosing this way, the light can only get through the characters and symbols where they are laser etched. But light is still able to transfer through the silicone from key to key because the switch keyboard is molded in all clear.

This the simplest and most economical solution.