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Comment by gray_-_wolf | Hacker News Reader

> It doesn't make economic sense anymore to use seven segment displays in new products, small TFT/LCD and even OLEDs are cheaper.

Maybe cheaper, but what about power consumption? I would have expected them to need significantly more, which might matter for battery-powered devices.

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I suspect that simple LCD displays have the lowest power consumption (see wristwatches, etc).

They are not even remotely comparable when it comes to readability/contrast.

For that we have Memory LCD https://www.adafruit.com/product/3502

While this display is really slick, it seems like it is still not available under multiple suppliers? If thats the case. that means its going to be more pricey than other options. I cant seem to find many cheap options on alibaba/aliexpress.

Apparently Sharp introduced the technology in 2009, so perhaps there's a patent expiring soon?

How do those compare on price though?

Well that one's from Adafruit, so probably 10x the price of what's commonly sold.

Unlit liquid crystal 7-segement displays are the lowest-power & lowest-cost solution. You're absolutely right. The person you're replying to clearly doesn't have experience in the low-power/low-cost embedded world. In that space even 1KB of SRAM is a liability.

> Maybe cheaper, but what about power consumption? I would have expected them to need significantly more, which might matter for battery-powered devices.

Seven segment displays are quite power hungry relative to what information they can display. LCDs sip power, the issue is their backlight.

Seven segment is a pixel layout.

LCD/LED are pixel types.

Seven segment LCDs are super low power, and can be made to reflect through ambient lighting.

Like how my calculator runs off of the the tiny solar panel that is built in and is powered by ambient light in the room.

I think some folks might be thinking of the older light-emitting 7 segment displays which used more power.

Ah my bad, I was thinking of the early zero power seven segment numeric tape printers.

The numitrons used a ton of power. Or was that VFDs?

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