Hi,
No, the black plastic around ICs isn't black by chance.
Einstein got his Nobel price on the photoelectric effect, which is
relevant in this case.
A few years ago I assisted in modifying a camera for an amateur
astronomer. Among the modifications, one was to turn of power for a
pre-amplifier, as the biased amplifier was also emitting a faint
infrared light that the sensor picked up and accumulated causing a
redish gradient over the whole screen - mathcing the radiation pattern
from the on-chip amplifier. By only powering on the amplifier before
read-out significantly reduced the effect to essentially zero.
Cheers,
Magnus
On 01/18/2016 04:11 PM, Bob Camp wrote:
Hi
Back in the 70’s I was involved in making LCD watches. The whole “photo”
issue had not been fully through through. One day our chief marketing guy for
the project was driving around in Phoenix AZ. He looks down and notices that
his watch is dead. Pops out a spare, puts it on, confirms it it working. Hangs
his arm out
the window and …. that one is dead as well.
We changed the die coat on the ASIC to an opaque version soon after that …
Light does indeed interact with semiconductors. It happens even on circuits that
you would not *think* are photo sensitive. Physics is nasty that way ….
Bob
On Jan 18, 2016, at 6:45 AM, Poul-Henning Kamp <p...@phk.freebsd.dk> wrote:
--------
In message <569bc23a.3030...@arcor.de>, Gerhard Hoffmann writes:
LEDs abused as References:
This is one of the most stupid ideas ever, because LEDs works both ways.
(Back when LED wrist-watches first came out, people soon discovered
that they would reset themselves when photographed with flash.)
If you insist on using LEDs as voltage references, the first thing
you need to do is to dip the LED in something which shields it 100%
from incoming light *including infrared*
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
p...@freebsd.org | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
