Recent content by zyxwv99

Thanks for the feedback everybody. It never occurred to me that the same technology is used in nightclubs.

http://www.getstarshower.com/?uid=D3BC8E1884C8DA72426B90329025B568&gclid=CInx4NnW1McCFUzmfgodTswDrQ&gclsrc=ds:wtf: http://www.youtube.com/watch?v=gRaTgfnuI14 Yesterday I saw this TV commercial for a plug-in device that looks like two lasers, red and green, with a "stars" attachment...

My first thought was methane ice. WIRED had an article about it maybe ten years ago. It's a single molecule of methane trapped within a buckyball-shaped water molecule (or group of molecules). If you take a handful of it and put it in an empty 1-meter weather balloon, then tie it shut, it will...

I've ordered lasers like that. They are for real. AliExpress has plenty of them, some as high as 20000mW. You just have to know how to read the ad. Take the price in cents and divide by 20. That's how many mW you actually get. If it's $30.00, that would be 150 mW. Plus or minus a factor of two...

It gets better further down, but the first screen-full (or two) is simplistic and heavy-handed, almost like a drill sergeant talking to juvenile delinquents at one of those boot-camps for juvenile offenders. "Listen up kids! I know you're stupid. That's why they sent you here. I also know you're...

What you're describing is known as "foveal tritanopia," the "central blue-blind spot," or the "blue-blind zone." It's normally about 0.25 to 0.4 degrees of the field of vision (the full moon is about 0.5), corresponding to the part of the retina called the foveal umbo or foveal reflex. Most...

I'm the one who revived the topic. I was already researching human vision in the near infrared on my own, and was amazed to find someone else had thought of the same thing. I hope your eye is okay. New interest: single-photon vision.

I tried watching the video, but most of it seemed to be about how brilliant minds of the past were misunderstood, the implication being that anything out of the mainstream must be brilliant. He didn't start getting to the point until more than halfway through a 14-minute video. That's why I kept...

It seems that the primary focus of your problem is the switch and how to control it. For that you might need to know what kind of electricity that switch is controlling. That would probably be electricity coming from whatever sort of batteries you are using. Knowing the battery type and how many...

Eye-safe has several different definitions. From a legal standpoint, an eye-safe laser is 0.4 µW (class 1). Anything higher and you could get sued if some kid looks into the beam. How far a laser can "go" depends on who or what is detecting it, for example if the laser is shined directly into...

That's one of the known companies that sells seriously underspec lasers. Reminds me of the 20,000mW (20W) laser pointer being offered on AliExpress for $13.95. With free shipping.

I think it was Ian Fleming who proposed the idea in 1956. Or Sean Connery in 1971, I forget, but the movie was called "Diamonds are Forever." The evil Dr. Blofeld has his minions steal diamonds, which mysteriously never turn up on the black market. Instead, they are used in an x-ray laser...

Re: Possible cheap 2-line 980nm/490nm pen On a completely unrelated tangent, I found some more info on human vision in the near infrared. Until today, the best info I had was Sliney (1976) where a 1064nm laser with 3mm diam. beam shined into 20-minute dark-adapted eyes needed an average minimum...

X-ray lasers are easy. http://upload.wikimedia.org/wikipedia/commons/1/13/Prague_asterix_laser_system-interaction_chamber.jpeg It's gamma-ray lasers that nobody has figured out yet.

Re: Possible cheap 2-line 980nm/490nm pen I've never heard of fluorescence being limited a specific wavelength range or direction. For all I know, radio waves could cause something to fluoresce in microwaves. I'm not saying this is the case, just that from what I've read on how fluorescence...