Re: Dead Black

I'm also concerned that there's no real seal between the lens holder
plastic and the PCB, but I can solve that easily enough with some
black paint that will wick into that joint.

I'd use larger lenses too, but we're mechanically constrained from
that.

If the seal is to keep out light, you're fine with black paint. However, if
it is for humidity, use an appropriate epoxy or sealing ring and check if
the rest of the lens is hermetic.

Marco
________________________
Marc Reinig
UCO/Lick Observatory
Laboratory for Adaptive Optics

"dbvanhorn" <microbrix@xxxxxxxxx> wrote in message
news:85892652-8f7f-4e1a-9c83-6cabc56c7284@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

In most cases the black plastic lens holder screws to the PCB, but
it's square base covers the entire image sensor chip.

That's how it is on these.

This base should block light from the mounting screws and solder joints on
the
PCB from reaching the image sensor surface.

On these, there are solder joints and vias near the imager, under the
housing.

The inside of the lens holder may be shiny black plastic which may not be
ideal for attenuation of stray light. However, cost is a driving factor
with
these types of components. To get a better optical black finish on
the inside would probably drive up the cost too much.

Well, I'm not that cost sensitive, I'm just trying to get a handle on
how much improvement I could get.
I have to use these in everything from barely moonlight to "staring
into the sun, on the snow pack, at noon"

I'm also concerned that there's no real seal between the lens holder
plastic and the PCB, but I can solve that easily enough with some
black paint that will wick into that joint.

I'd use larger lenses too, but we're mechanically constrained from
that.


.