Designing a focusable LED dive light.

[whitenoise]

[offtopic mode] You mean the poor Pound rate ?

Yeah yeah, rubbish isn't it? :shakehead

Michael, I could not see from the pictures can the batteries be removed from the photon? Also is it a solid battery pack, or does it contain individual batteries which could be replaced?

Thanks

 

[mbsub]

@ Whitenoise

Its a fix mounted solid battery pack. A use with normal alkali cells is impossible, because the voltage isn´t high enough.

Michael

 

[whitenoise]

Thanks for the info Michael. So if I get you correctly, the battery pack is internal, so it can't be removed, and to charge the light you simply plug in the charger to the torch?

 

[mbsub]

@ whitenoise

On the picture you can see the charging connector in the battery housing of the PHOTON.

Michael

 

[whitenoise]

Thanks again Michael. Is there any chance of seeing some beam shots of the light so we can see it in action?

 

[mbsub]

Of course i will show some beam shots, but its only a question of time. In the moment is much work.
Maybe i can make them on weekend.

Michael

 

[whitenoise]

Thanks Michael, looking forward to seeing them!

 

[mbsub]

Here is a beam shot for compare the spot (8°) and the flood with 36°.
Both beams are have not any spill.

Michael

 

[Packhorse]

Great shots Michael.

Are you using a custom aspheric or an off the shelf one?

 

[mbsub]

Great shots Michael.

Are you using a custom aspheric or an off the shelf one?

Its a custom aspheric lens.

Michael

 

[DaYerk]

By the way: which aspherical Lens is the right one for a SST-90? There are lots of plastic and glass lenses in the Flashlight DIY section of DX.

Why are some of the lenses so big (> 60mm)? Is bigger better?

For example: I have a 7,2V 10Ah Batterie in my diving light. It can deliver easily 50W or more. According to the limitations of the 7,2V my plan is to use a single SSR-90 with a 9A driver. The inner tube diameter is 70mm, the useable diameter of the front glass is 62mm, the max hight for the LED part incl. lens and heatsink is 50mm. With some heavy mods it could be maxed to 70-75mm.

Which aspheric lens is right? Sorry for being "half OT", but it looks like Packhorse is searching for the ideal lens too. It would be great if there is a way to focus the light "offline", which means: to open the Light and focus with a screw or something like that.

I like this idea better than glueing everything together. Because I think, I have to do some tests under water, to find out which focus is best in combination with the power of the Led.

 

[whitenoise]

Thanks for the beam shots Michael they look good.

 

[Packhorse]

There is no "right" aspheric for any LED. There is only the right aspheric for the application (if you are lucky of have had one built).
Wider aspherics will generally produce a tighter spot focus.
Aspherics with a shorter focal length vs diameter will generally be more efficient and gather more light.


Check out the specs on the KD or MG 50mm aspheric lens. My guess is by the time you add up the thickness of the aspheric, the focal length the LED and the thickness of the heat sink you will be well beyond your max length of 75mm.

 

[Linger]

Mbsub, I'm impressed with those beam shots.
Aspherics don't always play nice with these larger sized dies.

 

[DaYerk]

@Packhorse

Thanks for your reply. - It`s a bit OT, but i just ordered 4 parallel wired MC-E M binning for a good price. - No SSR-90 this time. Wired 2S2P it should be no problem to drive them directly from 7,2V 10Ah.

Enough power for a divelight. Trout made some beamshots with the MC-E and the 26mm lens from DX.

https://www.candlepowerforums.com/threads/210242

May be this will work better for me.

 

[saabluster]

Wider aspherics will generally produce a tighter spot focus.
Aspherics with a shorter focal length vs diameter will generally be more efficient and gather more light.

Width does not make the spot tighter. It is the focal length that does.

 

[Packhorse]

How so? Longer focal length tighter focus?

I have use aspherics with similar focal lengths but they produced very different sized beams.

 

[wes_wall]

This thread has gone bonkers. It is no longer a focusable LED dive light thread.

 

[saabluster]

How so? Longer focal length tighter focus?

I have use aspherics with similar focal lengths but they produced very different sized beams.

Yes. Longer focal point=tighter spot. Width will control how much light gets focused in that spot.

 

[saabluster]

This thread has gone bonkers. It is no longer a focusable LED dive light thread.

So true.

I designed a focusable element for the DEFT a long time ago I just haven't had the time to implement it because of time and money. It is based on rotating the head which acts on the internal components to cause a lens to come down over the LED and reshape the beam. This is a superior design than other lights because the beam shaper lens can move to the side and allow a straight shot to the main lens from the LED. Other focusable lights have the smaller optic always in line between the LED and main lens which is a compromised solution for maximum throw. I can vary the beam from DEFT tight to full flood(or anything in between) by varying the optic used to reshape the beam. I hope to be able to work with Will on this in the near future.