I am not an electrical/electronic engineer, so please bear with me as it might be pretty simple for you.
I have a monochromatic camera (www.qimaging.com/resources/pdfs/QICAM-12bitManual.pdf) which can be triggered (i.e. capture image) by a 5v TTL signal provided by an external triggering system (a function generator in my case: http://www.ms.sapientia.ro/elektronika/fileok/muszerek/cfg253_jelgenerator_leirasa.pdf).
So, basically I want to feed the camera a 5v TTL signal and make the camera capture an image (i.e. trigger) on the rising edge of the signal (High edge). I also have an external pulsed light source, supplying the required light for the image, which also needs to be synced with the triggering TTL signal on edge high mode (www.hsps.com/2006/pages/nanodren.htm).
I have come across a two issues for which I need help from you:
1) I am using a function generator with an in-built TTL output (BNC connection). So, when I monitor the function generator output, which is simultaneously connected to O-scope, camera and light source, the voltage amplitude is not 5v, but around 3v. That persists even if I set the function generator's impedance to High Z. I tried two different function generators and I get the same 3v. What's the reason behind this? How can I get an exact 5v TTL signal? I want my signal to be at least 5v as my external light source does not work consistently when the signal is below 4v. I already tried with 3v but the light source sometimes skip one pulse presumably because of the signal is insufficient. I heard somewhere that a pull-up resistor may solve my problem, but I have no idea about that.
Note: internal impedance of the function generator is 50 ohm.
2) Now the sync issue: the camera delay time is around 15 microsecond, meaning it takes for the camera 15 microseconds to open its shutter after receiving the high edge of TTL signal. On the other hand, the delay associated with the light source is around 2 microseconds. So, I won't get any image because the light has already been out when the camera shutter opens. So there is no light when the camera shutter is open. Therefore, basically I need to further delay the light source (say, 15 microseconds more, meaning a total of 17 microseconds) to be able to get image.
Thanks for taking time to read my post!
I have a monochromatic camera (www.qimaging.com/resources/pdfs/QICAM-12bitManual.pdf) which can be triggered (i.e. capture image) by a 5v TTL signal provided by an external triggering system (a function generator in my case: http://www.ms.sapientia.ro/elektronika/fileok/muszerek/cfg253_jelgenerator_leirasa.pdf).
So, basically I want to feed the camera a 5v TTL signal and make the camera capture an image (i.e. trigger) on the rising edge of the signal (High edge). I also have an external pulsed light source, supplying the required light for the image, which also needs to be synced with the triggering TTL signal on edge high mode (www.hsps.com/2006/pages/nanodren.htm).
I have come across a two issues for which I need help from you:
1) I am using a function generator with an in-built TTL output (BNC connection). So, when I monitor the function generator output, which is simultaneously connected to O-scope, camera and light source, the voltage amplitude is not 5v, but around 3v. That persists even if I set the function generator's impedance to High Z. I tried two different function generators and I get the same 3v. What's the reason behind this? How can I get an exact 5v TTL signal? I want my signal to be at least 5v as my external light source does not work consistently when the signal is below 4v. I already tried with 3v but the light source sometimes skip one pulse presumably because of the signal is insufficient. I heard somewhere that a pull-up resistor may solve my problem, but I have no idea about that.
Note: internal impedance of the function generator is 50 ohm.
2) Now the sync issue: the camera delay time is around 15 microsecond, meaning it takes for the camera 15 microseconds to open its shutter after receiving the high edge of TTL signal. On the other hand, the delay associated with the light source is around 2 microseconds. So, I won't get any image because the light has already been out when the camera shutter opens. So there is no light when the camera shutter is open. Therefore, basically I need to further delay the light source (say, 15 microseconds more, meaning a total of 17 microseconds) to be able to get image.
Thanks for taking time to read my post!
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