tasklight Luxeon head

My prototype of a new tasklight I'm working on.

First pic shows the base and the head/reflector. The base is where the Luxeon will be 'glued' down - the two small holes are for the wires that will run through the loc-line to the 'driver'.

Here you can see the 'pocket' in the head where the base slides in. There is room for the luxeon to fit - and the pedestal height where the luxeon sits is adjusted 'just right' to get the sweet spot of the reflector.

Dryfit of the base and head and loc-line.

And the required beam shot. It has a great even flood like beam - a bit wider than a mcflood and very even. The reflector is just the highly polished aluminium. The prototype has a HD R2H in it.


The final version will have a groove where a 22.5mm mineral glass lens will slip in and be epoxied to protect the reflector from grime/grit. The whole head will use thermal epoxy and straight epoxy to put it together.

I'm working on the electronics for it. It will run from 4 AA nimh batteries and be able to be recharged insitu from 12V (vehicle power) and will give about 5 - 6hr run time at full output. It'll have dimming capability etc. The 'driver' will be AVR based and have two switchers - one for the Luxeon and one for the fast charger for the nimh cells. I have a rough design for the driver/charger, just need to build a prototype & write some software. A fun project & I figured I'd share some pics of the first steps. I'll update my website as the design/prototype progresses:
tasklight webpage

george.

Interesting project georges80. You should have no problems with your heat transfer /ubbthreads/images/graemlins/grin.gif Just a little overkill... a little. Yes, keep us up to date with the build.

/ubbthreads/images/graemlins/thumbsup.gif /ubbthreads/images/graemlins/thumbsup.gif /ubbthreads/images/graemlins/cool.gif

Dan

Wow georges80, very nice indeed. Even made yore own reflector, eh? Cool.

My one suggestion would be to "glue" the mineral glass lens with something that is removable down the line, such as a single application of contact cement around the edge or similar, just in case you need to replace a cracked lens later, happened to me.

Just muh 2¢ here...

/ubbthreads/images/graemlins/thumbsup.gif /ubbthreads/images/graemlins/thumbsup.gif A man after my own heart! /ubbthreads/images/graemlins/grin.gif

- Don

very nice!

i have something on my shelf up in my room that is very similar. all i need is a wallwort to power it, but i just can't force myself to buy the $16 part /ubbthreads/images/graemlins/frown.gif

[ QUOTE ]
MR Bulk said:
Wow georges80, very nice indeed. Even made yore own reflector, eh? Cool.

My one suggestion would be to "glue" the mineral glass lens with something that is removable down the line, such as a single application of contact cement around the edge or similar, just in case you need to replace a cracked lens later, happened to me.

Just muh 2¢ here...

[/ QUOTE ]

Mr Bulk - thanks for the contact cement hint. I plan to recess the lens a little to protect it, but you're right, a less permanent 'glue' would be a smart idea. I might use one of the non-corrosive silastic type products to bed the lens in.

Yeah, made my own reflector. I'm trying to achieve a cheap to fabricate housing for a luxeon that would be rugged and weatherproof. Once I'm happy with the important design aspects, i.e. reflector and Luxeon height I'll hand the design over to a few mechie friends - that should be able to ensure the design is cheap to machine.

thanks,
george.

A quick update on my tasklight project. Got to go camping for a few days and figured it would be a good chance to try it out in a real application.

So, quickly put the prototype driver board into a box and mounted the control switch and loc-line to it. Taped the box to the side of a 6V 4ahr gell cell. We used the light quite a lot each evening at full blast, a bit on reduced reading brightness level and the whole night at 'night light' mode (drives the 1W Luxeon at <10mA) - we did this for 3 nights.

Here's a few shots of the prototype lashup




The following 3 shots are all F1.8, ISO400, 1sec exposure:

1st Shot - full bore. The bright spot on the ground is my son running a 2AA brinkman with NX05 optics and a 1W 350mA driven Luxeon. The white 'spot' on the right is the tasklight head.


Next shot is the tasklight at full bore lighting up the stove area. The light is on the far right - you can just pick up the orange of the battery.

And the same shot, but running at the lowest 'nightlight' level.


The drive electronics is AVR microcontroller based and I have a few tweeks to do to the software based on real usage - just 'features'. The AVR driver thread is here:
AVR thread

I found the head design to be very nice - you can be alongside the person using the light to read and you get no glare/blinding light in your eyes. Even after an hour or so at full blast the head is barely warm - I really want to try a 5W version /ubbthreads/images/graemlins/grin.gif. The nightlight mode is fantastic - all night at <10mA on the Luxeon is plenty of light to see the kids in a 4 man tent without being too bright.

The fun time - had a racoon visit a few times - I think that it is now seeing impaired after being hit in the eyes with a Mclux and a couple of other homemade Luxeon based torches...

george.

Really nice work! I'm very impressed. /ubbthreads/images/graemlins/thumbsup.gif

Very nice. This looks like a very useful light. Great work.

I like it! I have trailer on some remote property - with NO electricity.. I think I'm going to have to build somthing like this. The big battery keeps it nice and stable, not to mention a good run-time and the adjustable stalk would let me put the light where I need it. Gotta do it... /ubbthreads/images/graemlins/smile.gif

[ QUOTE ]
Slick said:
I like it! I have trailer on some remote property - with NO electricity.. I think I'm going to have to build somthing like this. The big battery keeps it nice and stable, not to mention a good run-time and the adjustable stalk would let me put the light where I need it. Gotta do it... /ubbthreads/images/graemlins/smile.gif

[/ QUOTE ]

Yep, it was definitely stable with the gell cell 'anchor' /ubbthreads/images/graemlins/grin.gif. The adjustable stalk makes it very useful - better than a lantern when camping. I hate lanterns, they put out lots of light BUT, the light is in your face! The run-time with the gell cell is great, with a fully charged 4Ahr gell cell the unit can run about 20hours at full 350mA output. I get excellent (93% or so) efficiency from my switcher at 6V. I'll have to change the software and set the output current upper limit higher - the head runs sooo cool that the 1Watter can definitely be overdriven.
My first PCB run will be just the switching regulator using the AVR uC. The next design will use a different AVR uC family member with 2 PWM outputs so I can also put a battery charger onto the same PCB (also uC driven). It will support either gell cell charging or NiMH charging.

This has been a fun project - the most useful non-torch I've built so far.

george.