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I bought this camera to experiment with, mostly based on the fact that it is considered to be a "Night Vision IR" camera. Now that I've received it, I am having a hard time finding out certain information about it.

Specifically, why does it have the extra pair of wires going to the lens cover housing? I have other similar PCB cams that lack the wires and have no claims of IR Night Vision. The wires go to a to wire connection on the PCB labelled "IR CUT", which says to me that it somehow filters IR. Now, I know that practically any CMOS camera is sensitive to IR light, but they are fitted with IR filtering lenses in order to give better (clearer) pictures in the visible spectrum.

If I hook it up to a transmitter, it works just like a visible spectrum camera does. I see no benefits when using it in the dark. I am thinking I somehow need to activate the IR CUT (or rather I suppose I would be deactivating it). Do I just simply apply a voltage to those pins?

If those wires do activate/deactivate the filter, how does it work?

There is another two pin connector on the PCB labelled CDS (images can be found at the link). Would they be for a photoresitor? How can I use those pins? I have searched for spec sheets online, but haven't had any luck. I don't really know what control chips it would be using. Does anyone have any similar equipment whose spec sheets could offer some hints?

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closed as off-topic by Andy aka, Leon Heller, Scott Seidman, nidhin, Dave Tweed Mar 28 '15 at 14:08

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions on the use of electronic devices are off-topic as this site is intended specifically for questions on electronics design." – Andy aka, Leon Heller, Scott Seidman, nidhin, Dave Tweed
If this question can be reworded to fit the rules in the help center, please edit the question.

  • \$\begingroup\$ Maybe they are to drive IR LEDs for night-time illumination. \$\endgroup\$ – Majenko Mar 27 '15 at 22:28
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    \$\begingroup\$ Maybe it should read IR OUT but the capital O is damaged? \$\endgroup\$ – Turbo J Mar 27 '15 at 22:36
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    \$\begingroup\$ C'mon guys this question is totally off-topic - it has nothing to do with EE. \$\endgroup\$ – Andy aka Mar 27 '15 at 23:07
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    \$\begingroup\$ @Octopus Cardinal rule: No datasheetNo sale \$\endgroup\$ – Nick Alexeev Mar 28 '15 at 5:24
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    \$\begingroup\$ @Octopus I've heard that people buy junk on the Internet, then go back to the Internet to find somebody else who would sort the junk out for them. Wonderful use of everyone's time. \$\endgroup\$ – Nick Alexeev Mar 30 '15 at 1:48
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It appears to be a mechanical shutter that interposes a filter in front of the lens.

Here are two links to similar products here and here.

These use a relay coil (or solenoid) to move the shutter. Unfortunately, this doesn't tell you how much voltage (or current) you should apply to your specific camera.

The second link shows 5V at 2.78W (0.556 A). If this is representative, then you certainly won't be able to drive it directly from a microcontroller. Most microcontroller outputs are limited to around 20mA. You would need to use a FET (or something similar) to switch the relatively high-amperage load.

Also, it seems that some of these require a positive voltage to assert the filter, and negative a negative voltage to remove it. In this case, you would need an H-Bridge to drive it.

There is a related discussion on the Raspberry Pi forums, which hopefully will help.

Good luck!

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  • \$\begingroup\$ That's exactly what it is. After following those links, I figured if I could wire up a photoresistor the right way I might get it to work. Even easier, if I just short the two CDS pins together, I hear an audible click and the image changes to BW with enhanced night vision, Sweet! \$\endgroup\$ – Octopus Mar 27 '15 at 23:55
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IR cut filters are for daylight. At night when you have your IR illuminators on you want as much IR light as possible to get to your sensor. During the day you don't want the IR light saturating your sensor you just want to capture as much visible light as possible. So on "nicer" lenses you will see an IRCut filter that you can move into position during the day and remove at night.

It's just a little galvanometer, if you apply voltage in one direction it energizes the coil and a tray with the filter slides away from the lens. Power the other way and it slides back to cover. Some might have springs so you only have to power it one way.

You may want to out a current limiting resistor in there and try it out with a voltage source.

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