What's new
What's new

Autocollimator: replacing incandescent bulb with LED?

LowEnergyParticle

Cast Iron
Joined
Jul 26, 2004
Location
Beaumont, near Houston
We have a Hilger and Watts TA-6 autocollimator that uses a 3.5 volt "GE-50" incandescent bulb for illumination. I am certain that I saw a thread a year or so ago where someone described how they upgraded the lamp to an LED. I can't find the thread.

Has anyone used an LED for this, and would you mind giving some details as to how you did it?

Thanks very much!
Dave
 
I have not done it.

A guy in a post talking about K&E said he had turned an adapter to fit his 1 cell mag light into a light source. I can't find the thread either but don't believe it was LED, just a superbright bulb. Don't see why not, try it!
 
These are some really high quality LEDs

http://www.luxeonstar.com/

They have some of the brightest on the market.

I believe you need a driver and an LED. I believe these are integrated together for easy installation. Take a look at these products..

http://www.luxeonstar.com/luxeon-flashlight-leds-other-flashlights-c-22_40.php

Also, after a quick google search, it looks like that style lightbulb is common for instrument illumination. Try dental and surgical supply searches. You might like a xenon bulb better.
 
We use CGE-605 bulbs in our TA51-2, and if you need some, let me know.
You can find an inexpensive LED flashlight that uses AAA or AA single cells that will fit the housing, I'm sure.
My Inova X1 is almost the right size, but may be a tad large to fit in.
No sense building a LED with driver assembly when the flaslight manufacturers have already done it and packaged it.
For the autocollimator, you don't need a super-bright source.
Post some pics when you get it going.
 
Howiesatwork:

Thanks very much for your kind offer of the CGE-605 bulbs! We still have several replacement bulbs, but if we get in trouble I will certainly keep you in mind. Thanks!

Apestate:

Great idea! The TerraLUX TLE-1S screw-base bulb you pointed out here at LuxeonStar certainly looks like a ready-to-go option. It seems it will simply screw into the existing bulb carrier originally provided by Hilger Watts! For $15.99, it's a hard option to beat. The driver circuitry is included in the base of the bulb. Screw the bulb in, power it with anything from 2 to 9 volts DC, and you're done. Regrettably, the Canadian firm wanted over $20 to ship via ground to the US. I ended up at LED-Replacement who wanted $18.95 for the LED but only $1.75 to ship it.

I will remember what you said about a xenon bulb possibly being preferrable - plan B if the TLE-1S doesn't work well.

Gentle:

Thank you for the confirmation; there are often PM posts that I know I've read but cannot find. In general the new board software seems to work very well, I wonder if there's a minor glitch with the search engine.

Thank you all for the information! I will post back results when I've received and installed the TLE-1S.

Dave
 
Last edited:
I should have clicked on the link provided by apestate... +1
Looks like a drop-in replacement to me, too.
I like the microptic autocollimator, but for doing the real big plates, we use an HP laser system. One of these days I should have someone show me how it works...
Either way beats a Planekator!
 
LED arrived and seems to work fine!

The LED I ordered a few weeks ago from LED-Replacement ($18.95 + $1.75 S/H) showed up yesterday. It seems to work just fine! :)

On the plus side, it's solid state, the light is very white with a bit of blue, and the driver/regulator/etc circuitry is included in the base of the bulb. Painless to install.

The only negatives I can come up with is that it is much brighter than the original GE-50 bulb, and changing the supply voltage on a regulated LED system does not change the intensity of the light. This is a mixed blessing; my eyes aren't so good anymore and the brighter light makes it easier for me to distinguish the reticule lines, but it also tires me out faster! I may fool around with a small dark filter, or join the 21st century with a CCD Eyepiece that connects to a USB port like this one.

If it works, pretty nice setup for $100! I'll have to machine an adapter to fit the CCD to the TAI-6 autocollimator, but that's not a problem.

Actually, my knowledge of optics is very small. I've got a couple questions if that's alright?

1. These eyepieces are intended for microscopes. Are the eyepieces for autocollimators different than ones for microscopes?

2. This particular one comes with a 0.5x reduction lens. I don't know if that's good, bad, or indifferent. Anybody know how this compares to an autocollimator's eyepiece?

3. The resolution on this one is 640x480. Like anything else, you can get more if you're willing to spend more! Does anybody have a feel for whether this resolution is enough to enable work that is at least as good as can be done with the naked eye & eyepiece?

Thank you again, everyone, for the help with the LED.

Dave
 








 
Back
Top