One way you can do this without another light source is to bounce a laser beam off a window or other things that are reflective.
In fact, the same principle can be achieved with radio. The Russians once planted a device in a wooden seal they gave to a US ambassador as a gift which, when a focused radio beam was aimed at it, would reflect and oscillate that beam due to vibrations in the air.
Vendor qualification isn’t easy but it’s also not especially difficult as long as you’re an American citizen with no criminal history. Figuring out the paperwork is half the battle.
Past that, the hoops you'll need to jump through depend a lot on which department is handling procurement. If you look at defense-related contracts, you'll also have to go through personal clearance (which can be difficult by itself at higher levels).
When I worked at Boeing, we even had them on the windows of offices that weren't being used for government projects. The company's commercial business was also a target for spying so they were very protective in general.
To this day, the company's laptops don't have cameras and they have a whole process that you have to go through to use a camera anywhere on company property.
Basically drowns out the room vibrations upon the window as it is a in direct contact. You can make your own with piezo discs and small circuit to drive them. That and high frequency will not cause added noise noticeable to humans.
Back in the 90's I found an old cardboard box full of radioshack electronics components and a paper schematic of how to put it together. I asked my dad what it was. He had been into an electronics hobby in the 1980s and told me that it was a amplifier to receiving laser light bounced off of a window for spy stuff. I couldn't believe it. The kit became my first significant soldering project. I got it all together and put my beloved laser pointer on a tripod and tried bouncing it in. I never did get it to the point that I could hear voices but boy could I ever hear cool vibration noises when I tapped the window.
It was extremely fun and I've been soldering things here and there ever since.
Thanks! It was a double-pane sliding glass door actually so maybe that did have something to do with it. Though, I also tried from the same side as the laser for most of my trials (i.e. laser and voice both coming from the inside).
In any building spies had access to there was a game of cat and mouse as (for example) spies would see people with radio equipment scouring rooms through the window as they heard their bugs go pop one by one.
Peter Wright (who wrote spycatcher) was the one who first got to look at The Thing; He actually broke it and had to make a new membrane for the microphone. He also invented (within MI5 at least) their technique for detecting superhet receivers (RAFTER), at one point they apparently were parked next to the soviet receiver.
I remember in the 1990s I was doing contracting work in SoCal and got a job at one of the big defense contractors near LAX. (Trying to remember which one... Hughes?) I lasted only one week as the building was totally secure - no windows at all. Life is waaaaaay to short to work in a hole like that.
Maybe someone with more info can fill in the details, but if I remember correctly, when Nokia changed their Silicon Valley offices to downtown Sunnyvale almost a decade ago, they were worried because Apple had offices in the adjacent building. If I remember correctly Nokia put in a bunch of security glass to prevent spying from vibrations in the windows. (There's some irony there, I know...)
Yup. It's fairly standard. For classified work the rooms and entry/exit protocols have to meet certain security requirements based on the classification level. No windows and no electronics are standard. No walls that is exposed to the exterior. I've been in room within a room setup when it was warranted.
In fact, the same principle can be achieved with radio. The Russians once planted a device in a wooden seal they gave to a US ambassador as a gift which, when a focused radio beam was aimed at it, would reflect and oscillate that beam due to vibrations in the air.
https://en.wikipedia.org/wiki/The_Thing_%28listening_device%...