The name of a U shaped switch that has an led on 1 arm, a light sensor on the 2nd arm and is controlled by blocking the light between the 2

[Dangerous Dan]

"The name of a U shaped switch that has an led on 1 arm, a light sensor on the 2nd arm and is controlled by blocking the light between the 2"

Hi guys, I'm working on something that these switches would be PERFECT for, but I can't remember the darned NAME of the buggers. Can anyone help me with that? I know they are commonly used in foot pedal switches, old game controllers, optical isolators, and are kind of like tiny versions of the garage door sensors. Any help would be appreciated. I've been searching for the name for a couple of hours now and I'm just NOT finding it.

Thanks!

Dan

 

[Nigel Goodwin]

Slotted opto-switch?.

 

[Mickster]

Photo interrupter, or opto interrupter.

What is a photointerrupter? |FAQ|ROHM Semiconductor

 

[Dangerous Dan]

Searches for both of those worked perfectly. Thanks guys! I need something similar to a magnetic reed switch but those are prone to failure after a while because of polarity trauma caused by being jarred too much. These should be GREAT substitutes and hopefully more reliable.

 

[Nigel Goodwin]

Searches for both of those worked perfectly. Thanks guys! I need something similar to a magnetic reed switch but those are prone to failure after a while because of polarity trauma caused by being jarred too much. These should be GREAT substitutes and hopefully more reliable.

They used to use them in VCR's, detecting rotation of the take up and supply spools (which had slots around their base for that purpose), and later ones often used reflective ones, with a circle of small mirrors round the base of the spools.

In both cases they used to get dirty and cause problems, the reflective ones were easily cleaned, but the slotted ones sometimes needed replacing.

So be aware it might not be as 'trouble free' as you were hoping?

Another alternative would be to use hall effect sensors, which would work with the existing magnets - and still later VCR's sometimes used those.