Lasers, we do love our lasers! From the classic Red, to the bright Green, to the sneaky, changing Violet we love the fact that we can have such a unique pointing device in our hands.
But laser pointers have undergone a few changes in recent years, and some of the changes may be hard to figure out. Times were they were all like flashlights: one end would screw off and you would insert the batteries (AAA or button cell). They would resemble this laser pointer:
There are a fair number of Laser Optics kits for classrooms on the market, but most of them are design for only a few purposes in demonstrating the properties of optics, lasers, and the like. The United Scientific Laser Optics Demonstrator works as a comprehensive optical demonstration system.
The core of the Demonstrator is a built-in He-Ne (Helium-Neon) laser. Unlike budget systems that may use a LED Laser (which can produce square shaped target dots). In addition the set includes a deflection system, ray optics board, and 30 optical quality glass components on carriers, three magnetic base supports and mechanical stage for wave optics.
The He-Ne laser is mounted horizontally in the demonstrator and the beam is diverted up towards the five mirrors. Each of these mirrors is only partially aluminized so that a fraction of the beam is deflected onto the white optics board to create a ray bundle. 
On the white board is a 360 degree graduated table for measurement. The table has a knob on the back of the board so that it can be rotated. In the dead center of the table is a mount where the various glass optical components can be mounted – Demonstration lenes (convex, concave) prisms, mirrors and other optical instruments. Fiber optics are also included.
In addition to these optical ray systems the Laser Optics Demonstrator can be used for several light wave experiments. The base holds the various magnetic base supports that are included with the demonstrator. These components include lenses, polarizers, an air wedge, bi-prism, interference apertures, obstacles. Many interferenc
e and diffraction experiments can be performed with these components. The laser is bright enough that most experiments can be held in a bright room, but extended patterns or diffractions may require darkening.
The entire Laser Optics Demonstrator comes in a metal carrying case that measures 15″ x 15″ x 13″.
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Once upon a time laser pointers were pretty much a high-cost luxury item. Back in the very late 80’s they could cost around $75-100 dollars for a simple red pointer that was nothing special. It was handy for those who had to do a lot of pointing work, but other than that it was a bit too much for most people to spend on a toy.
In the 90’s the prices on red laser pointers dropped a whole lot. Now you could get simple keychain models for under $5 and entertain your cat for less than a stuffed mouse. More fancy models still existed, but even they had come down in price. All of these laser pointers had one thing in common: they used a low cost red LED diode that projected a beam at 630nm. This was ok, but not a very visible pointer. Today a decent pen-length model can go from $10 to $30
Then came green laser pointers. At first they were very expensive: A basic model cost around $500 in 1999. But like the red models they soon came down in price, although they never quote reached the $5 level of the red models, they certain became more affordable. Now a green laser goes from $30-$150 depending on who is selling it.
Green laser pointers project a beam at a 532nm wavelength and generally have no greater output than the red laser pointers. Yet they are still very popular. Why? Because the human eye perceives the wavelength region around 532nm much better than the region around 630nm (red laser pointers). This video we made years ago illustrates this effect quite nicely:
Green lasers are bright enough that their beams can be visible under night conditions, so they are even used in astronomy to point towards objects in the night sky.
These days a third color of laser pointer has entered the fray (ignoring the very expensive ‘True Blue’ models, mind you). This is the 405nm wavelength Violet/Blue laser pointer.
405nm is not as visible as the 532nm Green Laser pointers, but 405nm does have other advantages. It is a wavelength that has industrial uses, and since it is a wavelength that is verrry close to the upper end of the human eye’s spectrum it actually is almost in the Ultraviolet spectrum. This has many uses, but one of the most interesting effects with how the human perceives the beam point. If it sits on a bright, white surface the point appears to be one color, but aim it at a not so bright, white surface and it appears a different color. This is an effect similar to what happens when you point an ultraviolet light at piece of bleached white clothing.
More fun, however, is what happens when you point the Violet/Blue laser pointer at popular Glow-In-The-Dark toys. We illustrate what happens in this video:
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Additional Note 8/26/14: Sadly this product has been discontinued by the manufacturer. There were some reliability issues but we feel they could have been solved. We are sorry to see this item go.
We were stunned when we first saw this little geek gadget. It just keeps on delivering goodies! Its the 7-in1 Laser Pen and that title doesn’t even begin to describe how much this little pocket sized tool can do!
First of all let’s have a look at it:
So far, it seems simple.
Its kinda in the title, so no surprise
Of course, it is in the description, so we are certainly going to have a laser pointer in this thing. And we do. A class IIIa 650nm laser pointer is at work here. Great for any purpose you might need a laser pointer for, which means pointing things out to friends or making cats go crazy.
Next up is the LED snake light. This is a standard white LED bulb that remains on after you push the button. The snake coil can be positioned almost anyway you like to shine light where you need it. Press the flashlight button again and…
Ultraviolet!
…you’ve got an ultraviolet light! This is another LED light that emits at 395-400nm and can be used to check special features on drivers licenses, credit cards, or to check UV sensitive invisible ink
Now of course, with all these gadgets and parts the old joke comes back about the watch with so many features it doesn’t have room to show what time it is.
Yup. It writes.
Well this should establish that this thing does actually have a pen in the laser pen, and yes. It does write! Mind you, you will have to unthread that cap. It doesn’t just snap off like many pen caps. And there is a reason for that:
Wow! It grows!
That reason is that the cap is part of the pen’s extending magnetic pick up wand! At full extension (this is not show at full extension) it is over 17″ long and the magnetic cap can pick up any ferrous item that isn’t too heavy for it. Here we see it holding a flat watch battery (it was all we could find).
That’s quite a list of features! But wait, you want more? Well we did say this was a 7-in-1 Laser Pen, and so far we only have five. Well if you unscrew the central body you get this!
That’s right, is a mini flat-head screwdriver! A 2mm flat head screwdriver to be exact. Handy for certain electronics and other small screws! But just in case you have to deal with electronics where a lot of philips-head screws are involved you can simply pull out the screwdriver head and flip it around to get:
What doesn’t this thing have?
A PH00 Philips-Head screwdriver! (You’ll have to take our word for it…this picture didn’t come out as well as we might have liked).
The Laser Pen has other features as well, such as a metal body and a sturdy pocket clip. The laser is FDA approved and all the lights run off 3 x AG3 batteries, the batteries are most certainly included!
Grab one of these awesome little gadget pens today!
We have recently added KHET to our product lineup! Khet has been around for a while but was always a bit on the expensive side. But the makers of Khet have now realeased Khet 2.0, which is a much more affordable game!
Like the best strategy games, Khet is very easy to learn but hard to master. Each side is given a special ‘Sphinx’ laser piece that ‘fires’ when you press it’s head. You also have several mirror ‘pyramid’ pieces, a couple of ‘Scarab’ pieces with mirrors on either side, a ‘Pharoh’ piece (which acts as the ‘King’ of the game to be protected), and a ‘Anubis’ piece that is used to block the laser. Players take turns positioning, rotating, and firing to try and illuminate the opponents Pharoh. Sounds easy? It is, but the possible reflections and positions make for endless possibilities int he game. You can even change the startup positions of the pieces at the beginning of the game to make for a different experience!
Khet is an excellent strategy game that works on the principles of optics. An option game addition can be obtained that turns the ‘Scarab’ pieces from mirrors into beamsplitters that send 1/2 the light through and reflect the remainder. That makes a huge change in the tactics of the game!
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