Suggestions to view an LCD display in the dark using IR

[rrz 0]

Hello everyone.

 

I have a bit of a tricky situation. I would like to use a remote camera to read the LCD display on a piece of equipment in an unlit room. The characters on the display are about 3/8" tall and 3/8" wide, and are in the dark. I've tried using the built in IR illuminators on the camera as well as some ambient lighting (which I can remotely turn on), but everything is washing out the display (please see attached image, the display looks more recessed behind the front window than it actually is). In other cases, I've had luck by changing the angle of incidence in which the camera is looking at the LED, but it's not working in this situation. Is there a filter I could use? Any other suggestions?

 

Regards,

Raymond

[rrz 0]

Slight type ...near the end it should read "camera is looking at the LCD display" instead of "camera is looking at the LED"

[tomcctv 187]

Hello everyone.

 

I have a bit of a tricky situation. I would like to use a remote camera to read the LCD display on a piece of equipment in an unlit room. The characters on the display are about 3/8" tall and 3/8" wide, and are in the dark. I've tried using the built in IR illuminators on the camera as well as some ambient lighting (which I can remotely turn on), but everything is washing out the display (please see attached image, the display looks more recessed behind the front window than it actually is). In other cases, I've had luck by changing the angle of incidence in which the camera is looking at the LED, but it's not working in this situation. Is there a filter I could use? Any other suggestions?

 

Regards,

Raymond

 

 

how is the lcd getting the image up i.e vga/ com is might be better for you to record from the source than using a camera pointing at a screen.

[bpzle 0]

what kind of equipment is it? chances are i may know how to work on it, or give you a better solution.

 

what kind of LCD is that? monocrhome, like this?

 

 

or is it a 7 segment lcd, like this:

 

 

try changing the angle of your camera. make the camera look straight at it, not looking down like it seems to be in your pic.

[Soundy 1]

I suspect the LCD has glass or plastic in front of it that's reflecting the IR and any ambient light you're throwing at it. If this LCD has its own backlight, you'd be better off finding a way to activate that.

[Tailbone215 0]

what kind of equipment is it? chances are i may know how to work on it, or give you a better solution.

 

what kind of LCD is that? monocrhome, like this?

Monochrome-LCD-Display.jpg[/attachment]

 

try changing the angle of your camera. make the camera look straight at it, not looking down like it seems to be in your pic.

 

 

Why don't you just use the remote control and monoriting software that comes with the radio? You're trying to overcomplicate the situation.

[ptzguy 0]

or is it a 7 segment lcd, like this:

[attachment=0]Monochrome-LCD-Display.jpg[/attachment]

 

try changing the angle of your camera. make the camera look straight at it, not looking down like it seems to be in your pic.

 

I have installed an IR dome looking onto the thermostat of a freezer in an abatoir. The display is a 7 segment LCD and looks fine level-on but about 45degrees to one side(the IR is deflected away from the cam). The IR shows what the Thermostat dial is set to.

Here was my brainwave - if the temperature rises above zero degrees the minus(-) sign will disappear... If the minus sign disappears(obviously a problem with the freezer) the DVR's motion detection is activated... The DVR sends the owner an email... His email provider sends him the email and an SMS text - great eh? Not just a pretty face!!!

[rrz 0]

Hi everyone,

 

Thanks for all of the questions and thoughts. I should have clarified upfront that this is a 7 segment LCD display (black segments) that is house in a control box which manages a piece of equipment. (I mention this last part only because I don't have the skills to tap the source which is feeding the display ... it's on a control board).

 

I've tried different viewing angles of looking at the display, but it's not working. (Trying different did work on another display, but not this one)

 

What I'm going to try next is to apply some anti-glare film to see if it helps. I'll reply back with the results

 

Thanks again!

[rrz 0]

make that a 7-segment monochrome display (black segments)

[rrz 0]

Unfortunately there is no backlighting available on the display

[Tailbone215 0]

Unfortunately there is no backlighting available on the display

 

That's easy to solve. First off I would scrap the idea of using IR on this. Secondly, the easy solution here is to take the cover off that houses the LCD display and add a few LEDs on the very edge of the glass display. This is how they illuminate them. This should solve your problem. If you want to take this a step farther, after all LED work is done, you can make a simple viewing cone like they had in the old days for the Tektronix O-Scopes. This will prevent any stray light from interfering with your cam.

[rory 0]

Have you tried zooming the lens right in on the LCD?

Change the lens if you have to.

[rrz 0]

I'll look into the LED option which could work ... any suggestion on the type of LED's to use?

 

In terms of zooming, I've tried but the glare effect is still present.

 

Thanks!

[Soundy 1]

This would be a bit of a crap-shoot, even if it's worked before, because for such a basic concept, there are so many different ways that LCD displays are put together. They operate on a polarizing principle, and some designs use a polarized glass or plastic cover as well, both of which have their own levels of reflectivity and angles of refraction, and all will respond differently to different types of light at different angles. I remember some car stereo models that used to have a black-on-orange LCD display under ambient light, but if it got direct sunlight on it, the display would look orange-on-black. Was pretty neat.

 

Something you could try, before hacking the LCD itself with LEDs, would be modifying the camera itself, replacing the IR LEDs with white or colored visible-light LEDs. Maybe test first with an LED flashlight right beside the camera (disable the internal IR LEDs), and test different colors with filters or colored plastics.

[Birdman Adam 0]

Have you tried shining lights into it at all angles? A few LEDs at the right angle may light it up nicely.

[bpzle 0]

What is the display for???

 

Unless it's some mad scientist's test instrument, odds are there a simpler, easier, cheaper way of monitoring whatever it is.

[Tailbone215 0]

This would be a bit of a crap-shoot, even if it's worked before, because for such a basic concept, there are so many different ways that LCD displays are put together.

 

This is a possibility, but I think that everyone is over-thinking this. I've modded many displays in my days using simple yellow or green LEDs and haven't run into any issues. Actually worked really well with very even illumination. I think what he is trying to do isn't complicated. He can get a few LEDs and resistor and have a go at it. If the visible LEDs show promise in even illumination, they will, he can go one step farther an try the IR LEDs and keep the IR cut filter open on his camera. There are many ways to go, just experiment.

[rrz 0]

As an update .... I've tried lighting the LED from different angles with different types of light, as well as using different filters as a last ditch effort (polarizing and different colors) ... with no luck. I picked up some LEDs and a transformer and will try the DIY makeshift backlighting approach as suggested and will let everyone know what happens.

[Tailbone215 0]

Try getting the LEDS on the edges of the LCD glass as this will act like fiber optics and distribute the light evenly. I am confident you will be please with the results.

[rrz 0]

I picked up basic white LEDs ... am I better off using colored ones such as yellow?

[Tailbone215 0]

Give them a try and see how they look. Thy are cheap enough to experiment with.