Advice on making laser ray box for teaching

[Robert100]

Next month I am going to be teaching my 9th grade "Physics First" classes about optics, and I'd like to use a set of lasers to show them how rays diverge and converge in various situations.

Students will literally be able to see things like this:
http://www.colorado.edu/physics/phys1230/phys1230_fa01/topic23.html

Frey Scientific sells what looks to be a wonderful device: It has 5 side-by-side, 1 mW diode lasers, all lined up next to each other. It makes five parallel lines that do not diverge (at least not to a significant degree over the length of a lab table!)

These are great to aim at lenses or mirrors for ray tracing, optics experiments, etc. The only problem is that each device costs $380, which is total garbage. These low power laser diodes only cost them $10 each at most, probably less.

Laser Ray Box Item #: 1552737821
https://www.schoolspecialtyonline.net/ECommerce;jsessionid=BE4D8356EAF9023000B9CC88941A1F8B


It occurs to me that I should be able to build a useful device with cheaper, lower power, pointer lasers. These can be purchased for $5 to $20 each. But the trick is finding cheap lasers with a useful on/off switch. All the cheap lasers I see have no real switch. You have to constantly put your thumb down on the switch to turn it on, and the moment you let go it turns off. Not convenient. Do you know of any affordable, small lasers, that can be turned on - and stay on until they are switched off?

I've never done this before, but I am thinking of picking up cheap laser diodes, and soldering them together to a battery, or some power source, but I don't quite know how to do this. Its supposed to be easy, but not having done this before, I need some sort of instruction. Any idea on where I might find good instructions, including photos?

Take a look at these cheap laser components: I was thinking of picking some up here, but I am open to any suggestions!

http://www.wholesaleforeveryone.com/Merchant2/merchant.mv?Store_Code=WFE&Screen=CTGY&Category_Code=lasermod

Thanks much for your time,

Robert

 

[mgb_phys]

You can't really beat the keyring laser diodes for price, the performance is pretty good as well.
I would take a few, drill holes in a block to hold the barrels so that it also holds down the on switch. You might have to rotate them to get them beams parallel, the diode isn't very well aligned to the outer case.
Then remove the end caps and the internal little watch batteries, solder a wire to the spring at the end of the battery compartment and another to either the case or the wire to the tailcap. You can then run them all from either a couple of AA cells (most are 4.5V) you can also switch them on and off easily with a switch to the new batteries.

 

[astrokreng]

I would advise you to first consider the safety precautions and regulations for using lasers in a classroom setting. It is important to ensure that the lasers you use are appropriate for your students' age and are not harmful to their eyes. You may want to consult with your school's safety officer or a laser safety expert for guidance on this matter.

In terms of building your own laser ray box, it is certainly possible to do so with cheaper components. However, it is important to keep in mind that the commercial device you mentioned may have been designed with certain safety features and quality control measures that may not be present in individual components. Therefore, it is crucial to thoroughly research and understand the components you are using to ensure they are safe and effective for your intended purpose.

One option for finding instructions on how to build a laser ray box is to search online for DIY projects or tutorials. You may also want to consider reaching out to a physics teacher or someone with experience in building similar devices for guidance and advice.

In terms of affordable laser components, it is always best to do your research and compare prices from multiple sources. You may also want to consider reaching out to a supplier directly to inquire about bulk discounts or special pricing for educational purposes.

Overall, building your own laser ray box can be a fun and educational project, but it is important to prioritize safety and quality in the process. Good luck with your project!