Enclosure for blind display

[Hina Shah]

Hi,

Context - The produuct that I am working on currently requires a blind display. They have LEDs on the back side with stencil on top of it, that creates graphics and projects them on to the white plastic. The display is visible only when the unit is turned ON. Else, it is a plain white plastic top cover.
Here are some example images.

Most commonly these are seen in Air conditioning units.
My question - What type of platic can we use for this top layer (ABS, PP, PMMA or other)? Will painting the part make it opaque to LED lights?

 

[itsmoked]

Your writing doesn't make it clear to me whether the examples are painted/stenciled on the inside or the outside.

That aside the effect is optical so it doesn't care what material you use, it just has to be properly opaque to make the effect work.

I believe many different plastics would fit that requirement which is good. Select the plastic for other mechanical and cost reasons.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[drawoh]

Hina Shah,

Your part will not work unless it is translucent. You can use translucent paint, possibly on a transparent part.

After this, you need to ask practical questions.
[ol]
[li]Does your part need to be resistant to ultra-violet light? Many if not most plastics are not. Lots of paints aren't, either.[/li]
[li]How subject is your surface to wear? If you require a rough surface finish, you must assume it will not stay that way. Paint wears off eventually, which is bad if it is functionally critical.[/li]
[li]What material does your fabricator like to work with?[/li]
[/ol]

--
JHG