Sourcing Odd Parts LEP's (laser Exciting Phosphor)

[DarkMode]

Out of curiosity, I had come across this technology from a Survival Facebook group posting.

I've been searching the Net for the unit and only found complete flashlights.

This is the same issue I've had trying to search for COBs / High Powered Leds for a safety sign (in design). 

Where are the nooks and crannies?

[tggzzz]

Out of curiosity, I had come across this technology from a Survival Facebook group posting.

I've been searching the Net for the unit and only found complete flashlights.

This is the same issue I've had trying to search for COBs / High Powered Leds for a safety sign (in design). 

Where are the nooks and crannies?

The method of producing light is the same as in all white LED lights: blue light is downconverted to white light by the phosphor.

From what I can see, it appears the claims are that the geometry of a LEP device allows a less diverging beam than with LEDs. I don't understand why that is necessarily the case.

But more importantly, why would you want a safety sign that emits light only in a narrow direction? Surely you want a safety sign to be easily seen from all angles?

[tggzzz]

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But more importantly, why would you want a safety sign that emits light only in a narrow direction? Surely you want a safety sign to be easily seen from all anglesThat's because there are different requirements. Signs can only be viewed in 1 direction, warning lights should be seen 360*, however practically this may not be feasible (IRL). Directional Long distance Warning Lights are desirable and Government rules apply. There are minimum distances and also max brightness rules.   

Hm. So what, exactly, is the half-angle from which your signs must be visible and need not be visible?

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From what I can see, it appears the claims are that the geometry of a LEP device allows a less diverging beam than with LEDs. I don't understand why that is necessarily the caseThat is the property of Lasers, they are Mono-Frequency and in Phase and it's a desirable characteristic. Led's, even narrow beam/band are not the same.

So what?

You ask about "excited phosphor" devices where blue light (from a laser) excites a phosphor. The photons emitted from the laser are not visible; only the photons emitted from the phosphor are visible.

Now, what is the "mono-frequency" and "in phase" of the photons emitted from the phosphor?

How do you make the phosphor emit the photons in only a narrow beam? Hint: you can't.

If "mono-frequency" and "in phase" photons really are desirable, then your best choice is to use the laser without a phosphor.

Thanks for the Questions 

That's a response I would expect from a troll.

BTW: the "Quote" button is there for a purpose.

[Marco]

From what I can see, it appears the claims are that the geometry of a LEP device allows a less diverging beam than with LEDs.

Smaller spot size. Sure, a standard convex lens can't capture all the light from that spot directly in a collimated beam, but what it can capture diverges less. You capture what you can and spread the rest out with non imaging optics.

PS. not saying this is what the OP intended, but that's why the flashlight nerds want it.

[switchabl]

A lot of designs are probably custom, along with matching optics. But Kyocera actually offers a fully integrated chip now (https://www.kyocera-sldlaser.com/). It's available from Digikey, Mouser etc...

[DarkMode]

Brillant, thank you 

[tggzzz]

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That's a response I would expect from a troll.
Having a Bad Day? 

Any response to my questions about what mono-frequency and phase you expect phosphors to emit, and the directionality in which they emit photons?

[tggzzz]

More Questions and no Answers, is this the level of help on here, in Beginners? 

And then you call me a Troll? 

I don't need to Answer your questions, are you the Forum Police?

Are you happy picking on newbies asking questions?

Do we have your permission sir?

Take care   

Your initial response was belligerent, and I responded with the same tone. You don't appreciate it? Well, neither do I.

"Physician, heal thyself."

[switchabl]

Ignoring the bickering for a moment, and to avoid (potentially expensive) disappointment for the OP or others who come across this topic, let me state this explicitly: these sources employ a laser to activate the phosphor but the light they emit has basically nothing in common with that from a laser. It is neither monochromatic (clearly, since it is "white"), coherent (spatially or temporally) nor directed (emission is approximately Lambertian).

The unique selling point is that they pack a high power in a small area (the 1000lm Kyocera has a 0.5mm diameter spot). As Marco said, it is the small spot size that allows you to create a pretty well-collimated (=low divergence) beam using a single convex lens which is desirable for applications like projectors, microscopy and search lights.

[tggzzz]

Ignoring the bickering for a moment, and to avoid (potentially expensive) disappointment for the OP or others who come across this topic, let me state this explicitly: these sources employ a laser to activate the phosphor but the light they emit has basically nothing in common with that from a laser. It is neither monochromatic (clearly, since it is "white"), coherent (spatially or temporally) nor directed (emission is approximately Lambertian).

The unique selling point is that they pack a high power in a small area (the 1000lm Kyocera has a 0.5mm diameter spot). As Marco said, it is the small spot size that allows you to create a pretty well-collimated (=low divergence) beam using a single convex lens which is desirable for applications like projectors, microscopy and search lights.

Precisely.

Another issue might be the longevity of the phosphor materials and the (epoxy?) carrier containing them. The whole point of their design is to have a very high energy density.

Presumably the OP's sign will be illuminated for a long time. IIRC the Kyocera datasheet doesn't mention lifetime.

[switchabl]

AFAIK Kyocera claim 10.000h @70% for the 500lm. That is in line with what I have seen for discrete solutions as well. Like with LEDs, I believe lifetime is strongly affected by temperature.

It is a very interesting product (within a specific niche).

[tggzzz]

AFAIK Kyocera claim 10.000h @70% for the 500lm. That is in line with what I have seen for discrete solutions as well. Like with LEDs, I believe lifetime is strongly affected by temperature.

It is a very interesting product (within a specific niche).

I only glanced at the 1000lm, so perhaps there isn't a conflict there. There's the old rule of thumb never to use the smallest or largest parts in a range, since those are likely to be on the edge of manufacturability.

 it is an intriguing component. Equally interesting are what the niche actually is, and the niche's limits.

[DarkMode]

Great Information, thanks 

[tggzzz]

belligerent - the feeling of being done wrong

If you think that's what "belligerent" means, I suggest you consult a dictionary, e.g.
https://www.merriam-webster.com/dictionary/belligerent
https://dictionary.cambridge.org/dictionary/english/belligerent