Pocket Projector Uses Raspberry Pi

Who doesn’t want a pocket protector projector? Nothing will impress a date more than being able to whip out a PowerPoint presentation of your latest trip to the comic book convention. The key to [MickMake] build is the $100 DLP2000EVM evaluation module from Texas Instruments. This is an inexpensive light engine, and perfect for rolling your own projector. You can see the result in the video below.

If you don’t need compactness, you could drive the module with any Rasberry Pi or even a regular computer. But to get that pocket form factor, a Pi Zero W fits the bill. A custom PCB from [MickMake] lets the board fit in with the DLP module in a very small form factor.

DLP chips use lots of microscopic mirrors that you can move roughly 20 degrees under computer control. So you can reflect light into the lens or bounce it away so it makes the image black. For color, an RGB LED cycles through the primary colors and you have to time your mirror movements to the color you want to project. Of course, the module takes care of all this for you behind the scenes.

The module can output up to 30 lumens (by default, though, it is 20 lumens) and has I2C and 8/16/24-bit parallel RGB video interfaces. If you don’t want to go with a custom board, the device supports the BeagleBone Black right out of the box. The DLP resolution is nHD. That is the mirror array is 640×360. While you might think the “n” stands for not, it actually stands for ninth, as in one-ninth.

The current release of the adapter board lacks an audio amplifier, although that may change in a future release. For now, you can play audio from the Pi via Bluetooth.

We are amazed we haven’t seen one of these cheap modules in a 3D printer yet. Or maybe a holiday projector project. Get busy on those and notify us on the tip line when you are done.

 

50 thoughts on “Pocket Projector Uses Raspberry Pi

        1. Actually they clearly state on sites like banggood that it supports 1080P input and then lists the hardware resolution.
          It is annoying if used in the title of course but it’s good if a projector can downscale for itself rather than you having to make sure to supply an exact signal.
          There are device who cannot downscale or upscale and it is actually rather annoying.

      1. Hi everyone,
        One of the issues with a lot of those Chinese projectors is that they aren’t really “HD”. Some claim to display 4K video, but of course it’s severely down-sampled and most only use a 320×240 DMD.
        The DLP from TI was the cheapest with the highest resolution.
        It won’t ever replace a $1000 projector; it lacks keystone adjustments, (which is quite critical for any setup) and not hugely bright.
        …. but bang for your buck is pretty good!

  1. “Nothing will impress a date more than being able to whip out a PowerPoint presentation of your latest trip to the comic book convention.”

    I get that it’s probably meant in jest and there’s probably an element of truth there as well but that’s kind of an inappropriate way to both insult and stereotype your readers.

    1. I’ve been a farm boy all my life but then I got into Belastok technical university. I’ve been a boy next door but then everybody got tied up whether they like it or not. Building robots is fun and no one should be ashamed that it doesn’t attract ladies. We really enjoy working with stuff and turning our deep dark fantasies into a reality.

      1. To expand on THAT – my question to the one holding this projector and powerpointing me his/her/its latest mugshots I would ask: Is *THAT* the resolution you look good at? Kind of blurry, isn’t it?
        Comon … who wants to project ANYTHING at 360 lines? That’s like publishing Lord Of The Rings through twitter tweets.

        1. The worst displays (Projectors, LCDs, etc) are the ones whose manufacturer lies to the video source and then tries to render ten pixels per pixel!
          I.e. trying to render 1080p or more on a 300×200 pixel display (of any visual output type). Completely unusable.

          Then there is that not so bad but still ugly issue with actual 1080p displays of the “TV” variant (Plasma, LCD, LED, etc) with the non square pixels and/or split-pixel types….
          Mainly with those screens that have chevrons as their pixels and the top of the pixel switches to max brightness before the bottom half so you get this net-curtain effect: especially useless when trying to graphics-edit across the room in a conference, meeting, living-room, etc!

          Let’s not get into the 1337×786 “HD” screens* with that half height band of pixels on the top and bottom of the screen with that huge pixel gap making the net-curtain effect available on laptops so bad you want to throw the laptop through a net curtain and out of an open window 20 stories high from a block of flats!

          *Nothing 1337 (Leet) about these land-filler screens!

          1. Basically anything China direct. I decided to take a gamble on a 640*480 projector for $15. Got it and it was 320*240. The dispute process decided in the sellers favor because the didn’t see the difference

          2. @erik johnson Now seriously, you know you won’t get 640×480 for $15 (yet), so why act surprised? I think the dispute resolution is based on that.

          3. If it’s too obvious it’s no longer a scam really.
            If I for instance sell you a foam ‘gold bar’ on the street for $2 did I really scam you because it turned out to not be real gold?

        1. Chinese lumen is actually 0.1 ANSI lumens. When it comes to batteries Chinese mAh is actually 0.1-0.3 normal mAh. I’ve seen 5000mAh 18650 cell, when measured it shows 1000mAh, also I’ve seen 12000lm LED flashlight that draws 20W, so is 2000lm at best. Theory confirmed :)

          1. Reminds me how the word ‘smart’ is just meaning ‘tracked and monitored by strangers’.
            I wonder why organizations like the CIA didn’t change their name to ‘International Smart Services’ yet.
            Oh wait, ISS, that’s in use already.

  2. One reason this evk might not end up in a 3D printer is because the dlp used is not rated for a UV source. TI makes plenty of components that could do that but would require a different kit. I actually reached out to TI and using a UV LED would significantly reduce the life of the DLP.

    1. Interesting. I did not know that. I wonder what the mechanism is? Does the UV degrade the surface of the mirror or perhaps weakens the hinge? Even then, for $100 if it were a 10,000 hour consumable, that wouldn’t be much worse than my laser printer cartridge.

      1. Martin below is actually right – looking back at my emails they claim the “optical engine” would degrade. The engine appears to be everything but the DMD, so optics, optics housing, etc. Those are purpose-built and this one simply can’t be used with a drop-in UV emitter (so they say.) Young optics makes a UV engine but won’t fit in the current EVK.

        Another thing I learned was the different DMDs are optimized for different wavelengths, so while it might reflect *some* UV, it won’t be as efficient as one designed for that purpose.

        All said, “shouldn’t” doesn’t usually stop the hackaday crowd 😁

    2. Probably more the plastic parts of the module. It could even degrade the plastic lens. The DLP chip itself is all semiconductor materials (silicon, SiO, SiO2, perhaps silicon nitrides) and metal. Many DLP chips work together with a HID lamp – they produce plenty of UV.

  3. For that price you can get a full projector with an Arm S905x running Droid load up Kodi or Netflix on it and it supports HDMI input VGA 800×600 and it’s 7000 Chinese Lumens IDK what they are but they’re brighter than that thing.

    1. I see full HD for about 200 online.
      I expect a weak lamp issues can be overcome by replacing it with something that has real output? Assuming it’s not a light that is too full of IR, but LED saves the day there I would think.

  4. does anybody know which gpio pins are not used by the tindie module, i would like to add some more parts to my raspberry pi zero, but i’m not sure which pins i could use to add them to

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.