Improving the keyboard background light

[rygD]

The reason you only see plain white here is the flash of the camera I used
The material is indeed semi-transparent.

Yupp, and it is on a white table. But it made me concern that you do not even see any indication of the backside like the buttons itself or the black paint showing through the underside in some way. So it must be pretty opaque. Well, the method may be correct (it really should work this way) but the material is just not adjusted. 

Didn't ED already have samples that were too transparent and which didn't diffuse the light, then he got the more "frosted" one?  I am pretty sure I saw a picture and comment along these lines with the partial sample keymats.

I had an explanation using fog and flashlights, but the point is you can't make the keymat transparent and expect the keys to light up properly. 

 

[bismuthdrummer]

Could the keymat material work as a lens?

It's possible but would have to be extremely expensive, and I can't imagine many if any manufacturers could even do it. Just having an index of refraction > 1 doesn't produce a lens effect, the material itself has to be shaped in a particular way. Just do some Googling for physics of lenses and you'll see what I mean. Those shapes with a different index would have to be placed in a particular location inside the keymat for each key.

This along with my notes above are based on a physics education over 10 years stale now, so grain of salt there. But I distinctly recall proving the theorem for total internal reflection on an optics test, so hopefully I'm not way off base here.

 

[fusion_power]

Didn't ED already have samples that were too transparent and which didn't diffuse the light, then he got the more "frosted" one? I am pretty sure I saw a picture and comment along these lines with the partial sample keymats.

I had an explanation using fog and flashlights, but the point is you can't make the keymat transparent and expect the keys to light up properly.

Yes, he mentioned that. However, the company still need to find the best mix of the material to make it work like it should. Again, it has been done before, there are many (black) rubber keymats outside  with working backlit. And I'm also pretty sure not every solution needs one LED for each button. 
I wonder why this seems to be an issue, there should be fixed and prooved values of material mixes to have an working backlit silicone keymat. Just pick these and use it.

 

[oskda]

From ED in OP : 'Instead of 1 LED for 4 keys, we'll use 1 LED for 3 keys. The downside is that this will increase the costs of the Pyra a lot... by 0,40 EUR.'

This might be impractical and a little daft but would it be possible to use 1 LED per key, pretty sure our devs could find some cool uses for this (things like only illuminating the keys required for game / app control etc.)

Must admit I've got no real concept if this idea would over complicate things or would  be simple as there are already loads of LEDs on the board.

I think to use 1 KED per key would be nice, because cost is low (¿ near 0,40€x9 = 3,60€ ?), and it would solve the problem without change in keymat, and without using a transparent keymat that iluminates  surrounding space out of keys.

Really I hate keyboard lights that iluminates the edges and surrounding space, and I think that in Pyra it will be even much worst because there is too much keys -light out- in a small space with a too near small display.

On other side: devs can't control each LED individually because it would requiere too much logic/chips to do so (and it isn't included on actual desing). So you can control only keyboard ilumination as a whole, and on other side the leds for notifications individually.

 

[lukey]

From ED in OP : 'Instead of 1 LED for 4 keys, we'll use 1 LED for 3 keys. The downside is that this will increase the costs of the Pyra a lot... by 0,40 EUR.'

This might be impractical and a little daft but would it be possible to use 1 LED per key, pretty sure our devs could find some cool uses for this (things like only illuminating the keys required for game / app control etc.)

Must admit I've got no real concept if this idea would over complicate things or would  be simple as there are already loads of LEDs on the board.

I think to use 1 KED....

Key-Emitting Diode?

 

[bismuthdrummer]

Really I hate keyboard lights that iluminates the edges and surrounding space, and I think that in Pyra it will be even much worst because there is too much keys -light out- in a small space with a too near small display.
 

As ED effectively said - and I agree - bleed is inevitable. I've got two backlit keyboards right now, one SteelSeries built into my MSI GT780DX and one CM Storm. Neither design even tries to hide the surrounding light. I haven't ever seen a design that hides it either. Cue the person with a counterexample in 3... 2...

What is important is that the tops of the keys have enough contrast (black the obvious choice) so that the letters are perfectly visible, so then the bleed is more like a backdrop. Not so much different from the wall of light coming from the computer screen.

 

[Binky]

Even if we did have one LED per key, they probably wouldn't be individually addressable. That would require extra PCB traces to the chip driving them, assuming there are sufficient pins available.

 

[oskda]

As ED effectively said - and I agree - bleed is inevitable. I've got two backlit keyboards right now, one SteelSeries built into my MSI GT780DX and one CM Storm. Neither design even tries to hide the surrounding light. I haven't ever seen a design that hides it either. Cue the person with a counterexample in 3... 2...

What is important is that the tops of the keys have enough contrast (black the obvious choice) so that the letters are perfectly visible, so then the bleed is more like a backdrop. Not so much different from the wall of light coming from the computer screen.

I think you can be totally right on desktop and notebook keyboards. But Pyra is different: it is a like a pure "membrane" keyboard. And I have seen membrane keyboards were no light goes out of symbols.

Here http://talk.maemo.org/attachment.php?attachmentid=33386&stc=1&d=1379155831
or here http://pockethacks.com/wp-content/uploads/2011/06/Nokia-N950.jpg
you have the example: you can see a keyboard (more like Pyra keyboard) without surrounding light.

It may be you are right, and  the surrounding light is OK, at least on notebook/desktop computer keyboards, even good (for example this keyboard surrounding light seems nice as you can see keycap shape: Thinkpad keyboard backlit ).

But some questions afraid me:

1/ They plan to use some more LEDs and the (partially) transparent keymat. What if it doesn't work and it is no sufficient other time? And if light distribution is not enough good? They have to start other time...

2/ We don't konw how good or bad it will be souronging light on Pyra keyboard. Initially we weren't to have that: the decision was no surrounding light. What if it is bad when done?
I like the keyboard like as we can see it now, and without risky about that surrounding light.


I see ONE LED for EACH KEY is a secure way to go, and it is cheap (I said "near 0,40€x9 = 3,60€", but I think that was wrong, it may be like 0,40€x3 = 1,20€). What do you think about this?

I am afraid if to increment from 1/4 LED/key to 1/3 LED/key (1), and the keymate change doesn't work as expected, and they have to done changes other time: money and more time lost.

(1): This implicate also to change circuit board. So, better go directly for 1 LED/Key and you are safe.

 

[Grench]

1 LED per key is not possible. The back side of the key is the contact/surface that touches/crosses/connects the two traces on the motherboard to register a key click. Thus, the LEDs themselves must be off-set in the area between keys - preferably on the diagonal/corners.

 

[fusion_power]

It's total waste imho to make 1 LED for one key. Waste of money, waste of energy, waste of battery time. It's the "Sledge Hammer"  method imho, nothing elegant. I know no mobile device that have this because it's usualy not needed. You can illuminate 3-4 keys with 1 LED just fine if done right.

Here http://talk.maemo.org/attachment.php?attachmentid=33386&stc=1&d=1379155831
or here http://pockethacks.com/wp-content/uploads/2011/06/Nokia-N950.jpg
you have the example: you can see a keyboard (more like Pyra keyboard) without surrounding light.
 

To be fair, these are looking  all like plastic keys, could be different technics behind.  However, there are enough good examples with painted rubber/silicone keymats.

These look decent:

 

[oskda]

It's total waste imho to make 1 LED for one key. Waste of money, waste of energy, waste of battery time. It's the "Sledge Hammer"  method imho, nothing elegant. I know no mobile device that have this because it's usualy not needed. You can illuminate 3-4 keys with 1 LED just fine if done right.

EvilDragon said: « we have 1 LED for four keys - but the light is not diffused enough to properly lighten up all keys ».

So I understand that some keys -the ones with LED closer-, get enough light. So if every key has one LED close enough -with 1 LED/key- then all them will get enough light.

« Waste of money »: ¿Like 1,20€ per Pyra? ¿Too much money relative to Pyra total cost?

« waste of energy/battery »: if you have 4 times more LEDs, you can drive them with lower energy.

A hint: 4 LEDs of 1/4 watt consume like 1 LED of 1 watt

Even with 1 LED/key you get the same light on every key: totally uniform light. With 3 keys/LED (0,33 LED/key) we dont't know if light will be evenly distributed.

 

[oskda]

It's total waste imho to make 1 LED for one key. Waste of money, waste of energy, waste of battery time. It's the "Sledge Hammer"  method imho, nothing elegant. I know no mobile device that have this because it's usualy not needed. You can illuminate 3-4 keys with 1 LED just fine if done right.

« Waste of money »: ¿Like 1,20€ per Pyra?

« Waste of energy/battery time »: 4 LEDs of 1/4 watt consume like 1 LED of 1 watt. If you have more LEDs -1 per key- you can drive them with less energy, and even they will last much longer (if they are equal type).

And the more important: we have a keymat yet. To build, test, etc other keymats and other improvements will cost time and money. And if they get wrong other time, it will cost even more time and money.
 

In this moment they could test if 1 LED/key is enough with actual keymat, and if it is, they can go directly by a SECURE WAY.

On other side: have you think that Pyra keymate has a transparent portion on top key. What if this gets wrong with light? : We test other keymat/solution to begin test/etc...?  Risky business.

PD: Really I hope I have no to say "I said it".

 

[_jr_]

Please go back to where ED and others explain again and again why a led per single key is not possible due to physical constraints.

 

[oskda]

Please go back to where ED and others explain again and again why a led per single key is not possible due to physical constraints.

I have gone back (this threat), as you suggest, but I can't find where ED explain ("again" or for 1st time) why 1 LED/key isn't possible.


On other side I can find people saying « waste of energy/battery », where ED said « as each LED wouldn't need to be as bright as before, so each LED needs less power ». It may be more people may need to go back.

Just in case, I assumed they are going to try a mix solution -ED said this-, so I am ready for possible extra-delays if this mix solution needs more changes than only adding 1 LED/key

 

[bzar]

Please go back to where ED and others explain again and again why a led per single key is not possible due to physical constraints.

I have gone back (this threat), as you suggest, but I can't find where ED explain ("again" or for 1st time) why 1 LED/key isn't possible.


On other side I can find people saying « waste of energy/battery », where ED said « as each LED wouldn't need to be as bright as before, so each LED needs less power ». It may be more people may need to go back.

Just in case, I assumed they are going to try a mix solution -ED said this-, so I am ready for possible extra-delays if this mix solution needs more changes than only adding 1 LED/key

It's said that the LEDs can't be directly below the keys because the contact pads for the keys are there. Putting them slightly to the side from the contact pad isn't that different from how they are now, as the LEDs would be between the keys rather than each key having a dedicated one. So it's not said explicitly that having one per key isn't possible, but rather that putting those in positions where they would make a difference isn't because of the contact pads.

 

[comradekingu]

I think his gripe is that 1 for 3 isnt an even solution. Slightly more than 2 is.    LED [button] LED [Button] LED [Button] LED [Button] LED

 

[oskda]

It's said that the LEDs can't be directly below the keys because the contact pads for the keys are there. Putting them slightly to the side from the contact pad isn't that different from how they are now, as the LEDs would be between the keys rather than each key having a dedicated one. So it's not said explicitly that having one per key isn't possible, but rather that putting those in positions where they would make a difference isn't because of the contact pads.

I know that LED can't be where pad contacts stay -it is obvious-. But EvilDragon said: « we have 1 LED for four keys - but the light is not diffused enough to properly lighten up all keys ». With that I understand that with actual design  some keys -the ones with LED closer-, get enough light. So there is a position, closer enough, that those keys get enough light (other keys are far and don't get light or enough light).

There is a difference from saying «not diffused enough to properly lighten up all keys» to «not diffused enough to properly lighten ANY keys»: I understand, with the original sentence, that SOME of the keys get enough to properly light them: the ones with LED closer. And obviously in those cases the LED is not under key contac pad as this is impossible.

PD: Also it is possible ED wanted to say other thing, something like "actually no one key gets enought light"  

 

[hmc]

Probaably you have considered that already, but just in case (as it's not yet been mentioned in this thread): Have you tried LEDs with a bigger light emission angle? This could help distributing the light more evenly. 

If I am not mistaken, there are even SMD LEDs with small domes of diffusing material on them, so that the emission angle is almost 180° and the light is already very diffuse. I recall having found such LEDs back then when I searched for LEDs for the Pandora keyboard light mod I made. But unfortunately I cannot remember the brand or type.

 

[fusion_power]

Probaably you have considered that already, but just in case (as it's not yet been mentioned in this thread): Have you tried LEDs with a bigger light emission angle? This could help distributing the light more evenly. 

If I am not mistaken, there are even SMD LEDs with small domes of diffusing material on them, so that the emission angle is almost 180° and the light is already very diffuse. I recall having found such LEDs back then when I searched for LEDs for the Pandora keyboard light mod I made. But unfortunately I cannot remember the brand or type.

Interesting.  Should not hurt to get at least some information about this.

 

[battmann]

are there going to be any other colors for the backlight on the keyboard?