Tiny Projector Teardown

projector

The team from Tech-On has taken the time to teardown two interesting microprojectors. The first model they tackled was the Optoma PK101. It’s based around a digital micromirror device (DMD) like those used in DLP. Separate high intensity red, green, and blue LEDs provide the light source. A fly-eye style lens reduces variations between images. They noted that both the LEDs and processors were tied directly to the chassis to dissipate heat.

The next projector was the 3M Co MPro110. It uses Liquid Crystal on Silicon (LCoS) technology. The light source is a single bright white LED. The projector seems to have more provisions for getting rid of heat than the previous one. The most interesting part was the resin polarizing beam splitter. It not only reflected specific polarizations, but also adjust the aspect ratio.

[via Make]

Game Boy Pocket Backlight

gameboy

[palmertech] and [Bibin] have both completed backlight projects for the Game Boy Pocket recently. The most difficult part of the transplant is carefully removing the reflective backing on the LCD. After a thorough cleaning, a diffuser and backlight panel were added. [palmertech] used a backlight salvaged from a DS, while [Bibin] built his own using LEDs. You can see his backlight in the video embedded below. There’s a disassembly video too.

Continue reading “Game Boy Pocket Backlight”

Working With VFDs

vfd

We love old display technology, like Nixie tubes, but they’re often difficult to work with because they require higher voltages than digital logic. Vacuum florescent displays (VFD) fall into this category. While not necessarily “old”, they are becoming far less common than LCDs. The main benefit of a VFD is that it actually produces light directly; it doesn’t require a backlight. You’ll find these displays on various players and appliances: CD, DVD, VCR, microwaves, stoves, car headunits, and others.

[Sprite_tm] had written off some VFDs, but recently revisited them with renewed interest. He started by testing what sort of voltage would be required to drive the display. It took 3V for the filament plus 15V to drive the grids. There are VFD controller chips available, but he wanted to get this working with what he had on hand. He had experience with older 40xx series logic, which can be powered by much higher voltages than 5V 74xx. His final schematic has three 4094 serial to parallel chips with an ATtiny2313 controller. A 5V power supply is dropped to 3V with diodes to drive the filament while a boost converter brings it up to 15V for the 4094s that switch the segments. While the code is specific to this display, it would be a great place to start your own project.

Giant LED Lamp

led

[guyfrom7up] must really really love LEDs. When he needed some lighting, which would obviously be LED powered, he chose to actually build a giant LED. Well, he didn’t actually build a giant functional LED, but rather an LED shaped diffuser for some high powered LEDs. He takes us through the process of first creating a wooden model, using that to create a mold, then forming the final diffuser.  The final product is very well done, and instantly identifiable by any geek.

[thanks Brian]

Digital Clock Building

clock

[punkky] has been documenting his adventures building digital clocks. They each use six 7-segment LED displays, but he’s been gradually changing how they are built. The first version used a CMOS BCD-to-7-sement latch on each display, which is tied to a PIC16F627a. For the next run, he added multiplexing, so he could drive all the segments using just thirteen pins. He’s posted a final schematic with code and details of how the clock timing actually works.

Cast Concrete RGB Lamp

lamp

[matthew venn] shows us how to create this cool RGB LED lamp. There’s nothing groundbreaking here, but some good information on casting the base out of concrete.  The body of the lap is formed by two thin rods folded in half, stuck in holes in the base, with a lycra sleeve slid over them. The final effect is quite nice and can be controlled by 3 knobs recessed in the front of the base. Information on the actual circuit used is very limited, as there are so many tutorials out there for that, but he does show how he mounted it all, and plans on releasing the source code soon.

A ShiftBrite Christmas

[youtube=http://www.youtube.com/watch?v=8PVC5jABuB8]

[Garrett] took 30 of his ShiftBrite modules and mounted them to his front fence for Christmas. The ShiftBrite is a serially addressable high output RGB LED. The individual modules are quite adept at applications like this where you’re stringing multiple lights together. They have identical buses on either side, specifically for daisychaining. The installation above looks great.