Analog Scope Stands In To For Laser Light Show

[Joey] likes to dabble in laser projection, building his own hardware and writing the software that drives it. One way that he tests his setup is by replacing the laser assembly with an analog oscilloscope. This allows him to ensure that the driver board is receiving data from the software, and translating it into the correct electrical signals to drive the motors controlling the mirrored redirection of the laser beam.

In the video linked above [Joey] walks us through this process. It starts by connecting scope probes to the digital-analog-converter card that outputs image data for the projector. From there the XY mode is used to map the two channels perpendicular to each other; the motors that these signals are meant to control have mirrors that also move perpendicular to one another. After adjusting the scale and the timebase you will see the pattern the laser dot is meant to trace.

[Joey] entered this in a Tectronix contest. There’s plenty of other interesting entries to browse though. If have an entry that you’d like to see featured, or if you come across any other interesting stuff, don’t forget to tip us off.

Screen Tracking Projector

[Jon Howell] came up with what he calls a gratuitous project which projects his name on his office door. The thing is, his office door slides on tracks so he made a projector that can follow the movement of that screen. He used a laser printer to make a black and white pattern that indexes the movement of the door using a quadrature encoder. When it senses door movement a servo motor rotates the projector to match the change in the door’s location. As you can see in the video after the break it works even if the door is moved quickly.

We do agree with [Jon], this is a bit much. But it might be something to build into smart white boards that are mounted on sliding tracks. We guess that if you don’t plan to change the message being projected, which is the case with [Jon’s] office door nameplate, this would be a great way to use the image projector build we looked at yesterday.

Continue reading “Screen Tracking Projector”

Phosphorescent Laser Painting

 

Here’s a simple and interesting idea that increases the visual persistence of a laser scanner image. Using glow-in-the-dark paint, [Daito Manabe] prepares a surface so that the intense light of a laser leaves a trace that fades slowly over time. He’s using the idea to print monochromatic images onto the treated surface, starting with the darkest areas and ending with the lightest. The effect is quite interesting, as the image starts out seeming quite abstract but reveals its self with more detail over time.

As evidenced in the test videos, the bursts of laser scanning are matched to the fade rate of the paint. Therefore it would seem that the time taken to “write” an image is directly proportional to the desired visual persistence of the final image. We wonder, by combining clever timing and variable laser intensity could you write images much more quickly? How hard would it be to use this for moving pictures? With the ability to create your own tiny laser projector, and even an RGB scanner, there must be a lot of potential in this idea for mind-blowing visual effects. Add portability by using a phosphor-treated projection screen!

Share your ideas and check out the test videos after the break.

Continue reading “Phosphorescent Laser Painting”

Vector Plotter With Lasers

[Hubert] sent in his experiments using HDDs, CDROMs, speakers, and other components to make an XY laser plotter. Those carefully reading will note, its not all three to make one plotter, but rather three plotters each using a separate system. The setups have their advantages and disadvantages, and [Hubert] is sure to point them out; including circuit diagrams and pictures to help you on your own trials.

There is a little difficulty in reading English not so good, but considering we’ve never seen a single-laser vector plotter done before (spirographs come close, and no one wants to wait 85 seconds) it’s still very impressive.

[Thanks TJ]

RGV Laser

[Carl] sure has come a long way with laser modifications, now introducing his portable RGV Full Colour Laser. Although it feels just like yesterday when he showed us his green spiro and his Lego diffraction grating projector.

But enough of the past, the RGV laser is built using a White Fusion Mixing Kit and his own Full Colour Driver Extension. We couldn’t find any circuit diagrams or code to build your own at the moment, but it appears fairly straight forward and you can always take a look at [c4r0’s] Colour Laser.

Blu-Ray Laser Keychain

blu-ray-laser

[Jay] hacked a Blu-Ray laser diode into a keychain enclosure. He found a heavy brass keychain light from Lowe’s and stuffed the diode and a larger battery inside. The existing batteries weren’t powerful enough, so he drilled out the endcap to fit a 200mAh 3.6v lithium battery inside. He also modded the power button to only momentarily turn on the diode. With the larger battery, the laser can run for about an hour between charges. In addition to a Blu-Ray lasers, he also has versions with a 200mW red diode.

Related: Laser projector zippo