device to simulate a photo frame

[rem736]

is there a device that you can set to show a photo when it's off? not on standby like a kindle...but when it's completely powered down. i was looking at the dory sign. but i'm not sure it will ever be released at this point.

[haertig]

I seem to remember some developing technology that promised this a couple of years ago. I haven't seen this in the real world though. But I haven't gone looking for it either.

You would still need power to change the photo being displayed. So a dead battery might have the device continuing to display its last photo, but you couldn't change the photo until you put a new battery in it. Which kind of negates the benefit of a "battery free" display.

If you have some photo you want to leave unchanged for a long time and not require a battery for displaying it, it's cheaper and easier to just print it.

[Kusuri]

i don't think there is such an device. but my idea would be.. buying an color e-ink display and then display a picture on it with a raspberry pi or similiar. if you use a small raspberry, you could put it in a case that looks similiar to a pictureframe (3d printed?) and then add a small battery to it.

[rem736]

it's ok with a dead battery. i'll just connect to a computer to upload the photo when i need to change the photo. usb power from a computer should be sufficient to power it up. i just need it to have the ability to display that particular photo when it's powered down deliberately or when power is suddenly cut when disconnected from power.

in fact, if there is a device that can be powered by usb power alone without a connected battery, that may even be better because i don't need a dead battery to eventually bloat up enough to explode. with the photo set, in theory, i should be able to pull the usb cable while the photo is showing (cutting out power) and the photo should be static until the next time i reconnect it to power.

i remember seeing on an original sony prs-500 a static page of a book when it was completely dead. this suggests that the user left the reader on that page until power was completely drained. and that page was still very readable months later.

[rem736]

Originally Posted by Kusuri

i don't think there is such an device. but my idea would be.. buying an color e-ink display and then display a picture on it with a raspberry pi or similiar. if you use a small raspberry, you could put it in a case that looks similiar to a pictureframe (3d printed?) and then add a small battery to it.

good idea, but once the image is set, because it is e-ink, i shouldn't need to supply power until i need to change the image.

[Kusuri]

Originally Posted by rem736

it's ok with a dead battery. i'll just connect to a computer to upload the photo when i need to change the photo. usb power from a computer should be sufficient to power it up. i just need it to have the ability to display that particular photo when it's powered down deliberately or when power is suddenly cut when disconnected from power.

in fact, if there is a device that can be powered by usb power alone without a connected battery, that may even be better because i don't need a dead battery to eventually bloat up enough to explode. with the photo set, in theory, i should be able to pull the usb cable while the photo is showing (cutting out power) and the photo should be static until the next time i reconnect it to power.

In theory a e-ink display with a circuitboard that gets it's power over usb should do the job then, or? if you change the picture anyway only over PC, a E-ink display stuffed into a 3d printed frame should work i think.

examples:

- https://hackaday.com/2022/10/31/infi...never-repeats/

- https://hackaday.com/2022/05/22/rece...k-photo-frame/

- https://hackaday.com/2021/04/11/a-fr...every-morning/

- https://hackaday.com/2020/10/30/colo...me-pranks-mom/

should in theory do what you want to do if you modify the examples a bit.

[rem736]

thanks. the second link (postcard picture frame) looks to be very interesting.

[haertig]

How long do you need this device to display a picture? Something powered by one of those lithium coin cells might work (if it existed). Or solar power. These would not be unpowered displays, but if your needs are something like "display an image for XYZ time, and allow the image to be changed" then you may be able to meet those needs in ways other than "unpowered". Unpowered is one proposed solution, but don't overlook other potential solutions in your quest.

[ottischwenk]

Originally Posted by rem736

is there a device that you can set to show a photo when it's off? not on standby like a kindle

With a Tolino Shine 2/3, after removing the back, the battery connector can be very easily removed and reconnected (for changing the image after the boot).
And with these Tolinos, the underlying Android 4.4.2 is very easy to uncover

[John F]

Originally Posted by rem736

is there a device that you can set to show a photo when it's off? not on standby like a kindle...but when it's completely powered down. i was looking at the dory sign. but i'm not sure it will ever be released at this point.

I think there is a hack for Kobo where you can set an image for the sleep screen. Maybe a patch could be done to eliminate the sleeping text. And another patch to disable the text that the device needs to be charged.

[Quoth]

Originally Posted by Kusuri

i don't think there is such an device. but my idea would be.. buying an color e-ink display and then display a picture on it with a raspberry pi or similiar. if you use a small raspberry, you could put it in a case that looks similiar to a pictureframe (3d printed?) and then add a small battery to it.

Mono eink about 16 shades.
Colour eInk about 4000 shades and lower resolution. Darker than mono if pastel shades and much darker than mono if saturated colours.

No battery is needed as the USB to change the photo can power it.

[Kusuri]

Originally Posted by Quoth

No battery is needed as the USB to change the photo can power it.

Well, my initial Idea was that he could change it over wifi as an example. It could connect to his local AP and he could then put a small ftp server or similiar on it and transfer the files onto it wireless. It could then change between the images automatically / in an interval.

Didn't thought he wants to connect it to usb each time (which can be annoying depending on how often you change the picture).

[rem736]

Originally Posted by haertig

How long do you need this device to display a picture? Something powered by one of those lithium coin cells might work (if it existed). Or solar power. These would not be unpowered displays, but if your needs are something like "display an image for XYZ time, and allow the image to be changed" then you may be able to meet those needs in ways other than "unpowered". Unpowered is one proposed solution, but don't overlook other potential solutions in your quest.

the dorysign will supposedly use coin cells. and this is actually what i want.
a device with no power other than when plugged into usb is fine too. the image would be rarely changed or very infrequently changed.

but the dorysign may be limited to show only their templated images and not any photo that i want to show. besides that, dorysign, just delayed their projected release date (due to needing to change the power source?).

i just don't want to use a device with a rechargeable battery that is not removeable because the battery will die faster than the device. coin cells are easily replaceable and no on-board power is fine if it can be powered by a usb cable alone when plugged into a computer. no wifi is necessary.