Transmitting Composite Video Via a Laser

Would it be possible to transmit composite video through a laser beam

Yes, of course. Optical telephone lines transmit video (and all sorts of other information) in many locations throughout the world.

This article discusses some of the issues.

Yes, it is possible. I built an aparatus in the early 70s to do just that, using a Pockels cell and a polarizer to amplitude-modulate the light. Detected the beam using a PIN photodiode. Won me my first airplane ride, it did! I was a junior in high school. Very fond memory.

Thats a shame. No pockels cells on Ebay.

I did find this though. Would this alone connected to an amplifier be suitable?

http://www.ebay.co.uk/itm/BPX65-PIN-Photodiode-/120998522205?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item1c2c12ed5d

Transmitting analog composite television signals would be a piece of cake today. No need to use a Pockels cell, you can modulate a diode laser directly. My laser back then was a home-built He-Ne job using a Metrologic 0.5 mW tube. Had to immerse the damn thing in a magnetic field to keep the polarization from rotating.

What type of laser diode and sensor would I need? Also, what electronics am I going to need? I am needing something with the bandwidth to support video. It is about 6 Mhz of bandwidth I am needing.

There's a tale of a young apprentice who demanded of his teacher the world's knowledge whilst standing on one foot...

You've got the entire Internet before you, and yet here you are, asking for what is essentially the complete design? Shall I shop for the parts also, and serve them to you on a silver platter with fresh-cut flowers and a lace tablecloth?

You do the research first, then come back if you have any questions which you simply cannot answer. You'll not learn a single thing if it is handed to you, I guarantee it. You'll learn plenty if you do do it yourself and you'll proud that you did. You've got resources at your disposal that were scarcely dreamt of thirty years ago. Use them. Relying on someone else only makes them more expert, not you.

I will just buy an IP camera and attach a yagi antenna to it.

or you could use

http://www.wisc-online.com/Objects/ViewObject.aspx?ID=CIS5308

I haven't read this but look here it might help

Today's fiber optic communications uses lasers and photodiodes to do just that. You can put whatever you want on it...video, audio, data. I can't see why you couldn't use the same principle (even identical) only operating at different wavelengths and adjust the circuit. Chose your transmitter laser and photodiode to suit. I can't see how you will get a stable communication link as it will be difficult to align and calibrate the laser to point directly to the photodiode...and consider falling leaves, dust etc breaking the line.

optical fibre works on same concepts (digital to then electrical signal are change in formof light again same modulation and demodulation

I am just struggling to find an op amp with a wide enough bandwidth to support video.

Ok...Here's one that we use from Texas Instruments

Well,the laser light may be considered a high-frequency carrier, for example, a light with lambda = 1.5 micra, has a frequency of ~200Thz. Any signal to be transmitted by that carrier (for example by modulating the amplitude of the light with one video signal) can not occupy 0.01% of range offered by the carrier. So you can transmitte your signal. LED light is another source that you can use without problems.

Or you could use a complete system like this

http://www.westermo.net/dman/Document.phx/Brochures/Fiber+Optic/Fibre+optic+brochure+ENG.pdf?folderId=%2FBrochures%2FFiber+Optic&cmd=download

This brings back memories.

Wrote a paper in 1972 on this very subject, based on my research at the local uni. They were quite generous in letting me, a nerdy, long-haired high-school junior, use their lab facilities. Today? Probably not.

My lab gear consisted of a polarization-stabilized He-Ne laser, a Pockels cell with amplifier to modulate the polarization angle, followed by a fixed polarizer to amplitude-modulate the beam and, at the receiving end, a PIN photodiode and associated electronics. My paper won the regionals along with five other students (two from each state, three states in our region) and so we got to compete in the Nationals. It was my first airplane ride and the first time I tasted (way too much) scotch. Very fond memories!