[REVIEW] Acebeam W10. 1KM of throw, in your front pocket. 21700/18650, USB-C charging.

I believe it can if it is a two-stage system with an intermediate image. The first (very short focus) lens creates a reduced size intermediate image that is projected by the front lens of the light.

Edit: on second thoughts it will not work because the reduction step by the first lens requires a limited incoming beam angle, so the secondary virtual light source (the intermediate image) will be reduced in size but the luminance will be the same. netto result: lots of light wasted and a smaller hotspot but without throw increase.

This is the lastest one that was made

That is Endermann’s Optofire, it does not use a double aspheric lens, just a single aspheric lens for projecting the hotspot. It does include a Wavien collar but that is a completely different piece of optic, has nothing to do with the imaging of the led die.

Depends on F#.

It does the same principle as a double aspheric, Two focusing points.

I don’t think the original thread that someone did on double aspheric lenses survived in CandlePowerForums.

Hi, I made the Lightcanon and the Optofire :slight_smile:
They don’t use double aspheric, they use a single aspheric and a wavien collar.
Only one focusing point.
The collar reflects unused light back at the LED, so the same focal point as before.

Something like this uses a double aspheric: Sold/Expired - Mjölnir - Custom made Searchlight with Lens-System | Candle Power Flashlight Forum
The double aspheric system does not increase lux, it increases lumens.

The wavier collar reflecting the unused light back at the led until it makes it out in a specific direction, changes the beam pattern and refocuses the light, atleast that’s my understanding.

Double aspheric increases lumens that hit a specific spot so how does that not increase Lux.

With a wavien collar the beam pattern does not change, nor does it refocus light.
Since it is all bounced back to the LED, the light that is bounced back increases the led intensity by bouncing off of the LED again.
Both before and after it is coming from the area of the LED, so the beam just becomes brighter and nothing else changes.

With a double aspheric you do get more lumens but they are not “in a specific spot”, they actually are spread out more.
If you compare a single aspheric to a double aspheric, the double aspheric will project more lumens but the projected spot of light is bigger.
It is a linear relationship, more lumens -> more area = same intensity.
Since lenses aren’t perfect having the second aspheric will slightly reduce the light transmission and total lux.

Reflecting the light back at the led until it makes it out the hole, does change the beam though, your just running a reflector backwards creating a tighter hotspot.
Any kind of reflector will help throw light but they all change the beam in some way.
I don’t disagree that two lenses means light loss for each lense that the light passes through.

No, no tighter hotspot, exactly the same size. Brighter but not tighter. The wavien collar is not part of the optical system that projects light from the led to the hotspot.

No, not any reflector will help throw. In a lens light most reflectors will make just a secondary beam, that is: rings.
No, a properly focused collar used with a symmetric LED dies does not affect beam shape.
Why?

  • The light that would be originally in the beam - is unaffected. The collar reflects only the light that goes towards flashlight body.
  • The light reflected by the collar focuses on the LED. The LED’s phosphor absorbs the photons and re-emits them in a random direction. Some of them are re-emitteted towards the lens and increase throw - w/out affecting the beam. The others are lost and don’t affect the beam either.
  • There’s light not absorbed by phosphor, reflected off LED dome etc. It may bounce around the light several times, but it’s always LED-reflector path unless it goes from the LED towards the lens. In which case it increases throw w/out affecting the beam.

The light must get through the collar, it’s not magic, it makes it brighter by refocusing the light out an opening at the end. It doesn’t create lumens, it’s gathering up the stragglers and putting them in a narrower path. It definitely still requires an aspheric lens to create a tight beam.

Same thing the first of two aspheric lenses would do but more efficiently

I agree but I’m not talking any reflector and an aspheric lense, I was just saying that, by it reflecting it back at the source until it heads out the end of the collar (which is a backwards reflector) your focusing the beam.

Considering it culminated all the light and projects it out too the lens, how am I wrong by saying it’s creating a tighter beam. It’s functionally a projector before it gets to the lens

The small lens (we call it “pre-collimator”) needs to be spherical, not aspherical. That is how Vinz always did it. I have also had a light made using such a second lens. It works great for the focused mode but makes the defossused mode a bit more ugly.

These effects are seperate. The additional light coming out of the opening is created by the blue part of the spectrum of the LED hitting it again and being converted to more yellow-green light (it changes direction after the conversion, it’s scattered). This increases the intensity and also dramatically changes the tint (more yellow-green).

If you used a mirror (collar) that doesn’t reflect the blue part of the spectrum there wouldn’t be a large increase in Luminance. You would just cut off 75% of the LEDs total emitted light.

Changing the tint doesn’t add brightness though, so it is infact pulling light that would be in the spill and putting into the main beam.

I don’t think it would cut brightness, unless your converting light that’s not in our visible spectrum into seeable and usable light. But Led’s Don’t have that

This is a great torch. Buy it and don’t worry (just don’t expect much spill). lol

The light that the wavien collar collects would not be spill.
It would hit the inside of the head of the flashlight and be completely wasted.
This light does not come out of the flashlight because it does not go through the lens.

A collar reflects the light back at the LED projecting the exact same image of the die on the LED.
It does not make a smaller spot or a different beam, it just makes the LED brighter, and the projected spot brighter.

The spill of a beam is the light that hits the inside of the head, so why are you saying no? I’ll reword it one more time. Your Wavian collar, collects the light, aims it at the lens. Preventing waste, in essence projecting it onto the lens.
So please stop saying it doesn’t. You are redirecting output so less is wasted, I don’t no why you keep disagreeing then rewording it. Makes me feel like I’m dyslexic up in here.

It’s definitely more efficient then using a small aspheric lens close to the led, then a second one for final focus. It’s doing the same job just more efficiently. If you don’t believe me that’s fine, it’s an idea someone much smarter than me came up with close to a decade ago.

No, it collects light and aims it back to the led die. In the die most of this light is absorbed and converted to the different colour and then send out again in random direction. Please accept that that is a completely different, and much more going on both physically and optically than simply “collects and aimed at the lens”.