Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers



Help identify my HeNe Laser

Benjamax

Well-known member
Joined
Aug 16, 2020
Messages
252
Points
63
A distant relative gave me this old HeNe Laser many years ago that was being used in the 1990s.
The laser has no sticker or other markings on it except "Spectra Physics HeNe Laser" on the front.
Also came with the original Spectra Physics transformer. Sticker on it says Model 229-7P.
I searched the model and found the transformer being sold here and there but nothing about the laser.
Mine has a hole on the sticker where the first digit for the current is, but from online images it says 60mA / 120V. So it feeds 7.2W to the laser - What does that mean for the actual optical output? I have no LPM or a scanning wavemeter.
Would be happy to know what this laser was used for too :)

Edit: kept searching, actually found something right after posting this. On ebay 2 similar looking lasers. One says model 196-2 and the other 105-1
"Spectra-Physics-196-2-Laser-"
"Spectra-Physics-HeNe-laser-TESTED-GOOD-Siemens-Uniphase-JDS-solid-state-diode-"
Also found specifications for the 105 here
/brochures/SP105L1984/sp1052.html
could not post links due to low number of posts in the forum.
So seems like they made more than one laser with an identical looking tube, so without the sticker I guess there's no way to identify. still wonder what it was used for.
 

Attachments

  • 862d401f-de35-4bc4-8e03-e833f7975889.jpg
    862d401f-de35-4bc4-8e03-e833f7975889.jpg
    101.8 KB · Views: 17
  • d07db0ac-a2fb-4606-b956-0282235756dc.jpg
    d07db0ac-a2fb-4606-b956-0282235756dc.jpg
    110.7 KB · Views: 14
  • e0e1d017-a417-4363-8538-0eb48b96c609.jpg
    e0e1d017-a417-4363-8538-0eb48b96c609.jpg
    74.6 KB · Views: 14
Last edited:



Mattronium

Active member
Joined
Dec 12, 2012
Messages
747
Points
43
The specifications give it at 1.5mW or 2mW at 632.8nm. Although the power can sometimes be higher than specified, but not by much (3-4mW max likely).
Does the laser work?
Sam's laser FAQ is always the go to resource for HeNe info.
 

hakzaw1

Well-known member
Joined
Apr 2, 2009
Messages
10,490
Points
113
Good find and share Matt--



Sam has LIST= just measure
the Length and Diameter.
when you see 'class??' you will only know the MAX it may be & NOT likely the correct mW==its an 'up-to' power.
'Transformer' is correct but most call the it the PS or Power Supply.

it not common that the lables got removed. NO point in doing that. EXCEPT to decieve.
Trying to get more than it is worth.

I have two REO greens and a Yellow HeNe@ a few mW-- I bought from Sam himself and in person at SELEM

LOTs of reds. 4 Argons including a 145mW <ML making six lines.

IF you are a speed reader you MIGHT ...read eveeything at Sams in about a week or two --its massive check it out!!https://r.search.yahoo.com/_ylt=Awr...rsam.htm/RK=2/RS=.bzdFsYfqlWA4BcLlkMAUIvyziA-



I found a listing like that so I sent a link to Sam-the seller wrote--'untested power unknown'
Sam pointed out that the seller was a liar.. he had the PS listed..that was kind of Sam. . But he went further and linked me to some listing that were a better deal. He gave me the PS specs and one came up for auction-- the red HeNe lives!! I won both the head and the PS Sam told me to not bid over $??- I did not have to.
 
Last edited:

Benjamax

Well-known member
Joined
Aug 16, 2020
Messages
252
Points
63
Yes the laser works quite well.
The dot appears, to my eyes, brighter than the one produced by a cheap laser of 650nm/3-5mW. Perhaps because the 632.8nm is closer to the green than a 650nm? also could be the difference in collimating each one achieves.
So I was surprised to learn HeNes are relatively weak. Especially the models that look like mine. Though on a high humidity night the beam is ever so faintly visible by looking along the axis of the laser.
I have no idea how the labels were removed. The laser was on it's way to the landfill but that relative remembered I liked gadgets.
Happy it's not a monster because he gave it to me many years ago when I was 16 and knew absolutely nothing about laser safety except of course the no brainer of not shooting it directly into my eyes but that's it. I stared at its dot for way too much.
 

ultimatekaiser

Well-known member
Joined
Mar 10, 2013
Messages
2,880
Points
113
Spectra-Physics used to make the best lasers... I have some of the oldest ones they ever made. Truly astonishing craftsmanship at times, much like tektronix stuff.

the 196 is a great tube, I think most of them tend to do about 3 mW new iirc.
 

kumowoon1025

Member
Joined
Mar 12, 2012
Messages
195
Points
18
The specifications give it at 1.5mW or 2mW at 632.8nm. Although the power can sometimes be higher than specified, but not by much (3-4mW max likely).
Does the laser work?
Sam's laser FAQ is always the go to resource for HeNe info.
So do HeNe tubes maintain output power fairly well over possibly multiple decades? Does firing it up once in a while, or leaving them in a closet with dust piling on them (like I do) affect that at all? If so, which is better?

Or do you mean since their output was probably over the specifications when it was manufactured that even after a long time they will meet the optical output power or more? (Is that why they made them like that? So even if it became gradually weaker it'd still output at least the rated power?)
 

icecruncher

Well-known member
Joined
Jan 2, 2008
Messages
1,411
Points
83
So do HeNe tubes maintain output power fairly well over possibly multiple decades? Does firing it up once in a while, or leaving them in a closet with dust piling on them (like I do) affect that at all? If so, which is better?

Or do you mean since their output was probably over the specifications when it was manufactured that even after a long time they will meet the optical output power or more? (Is that why they made them like that? So even if it became gradually weaker it'd still output at least the rated power?)
1 Yes - it depends and
2 Yes

If they are a hard seal on the frit (where the glass meets the metal) they can last for decades without being used on a shelf. They also tend to have a very long life span especially if they are allowed to run continuously, or for long periods as opposed to constantly starting and stopping them.

A soft seal HeNe needs to be run much more often or they will usually have more problems.

Most HeNe tubes made in the last 20-30 years are hard seal.

When the tube are first produced they will usually output above spec. That is the case with most quality lasers, not just HeNe tubes. Anything from DPSS to Argons to Commercial Projectors are usually advertised below what it will actually do. Many will come with a physical sheet that shows the one you purchased and actual power.

I have a couple new HeNe lasers like that, some of my DPSS lasers are like that, my Kvant projector came with a spec sheet.

You will probably not get that kind of support and spec from cheap Chinese diodes and Ebay items.
 

ultimatekaiser

Well-known member
Joined
Mar 10, 2013
Messages
2,880
Points
113
1 Yes - it depends and
2 Yes

If they are a hard seal on the frit (where the glass meets the metal) they can last for decades without being used on a shelf. They also tend to have a very long life span especially if they are allowed to run continuously, or for long periods as opposed to constantly starting and stopping them.

A soft seal HeNe needs to be run much more often or they will usually have more problems.

Most HeNe tubes made in the last 20-30 years are hard seal.

When the tube are first produced they will usually output above spec. That is the case with most quality lasers, not just HeNe tubes. Anything from DPSS to Argons to Commercial Projectors are usually advertised below what it will actually do. Many will come with a physical sheet that shows the one you purchased and actual power.

I have a couple new HeNe lasers like that, some of my DPSS lasers are like that, my Kvant projector came with a spec sheet.

You will probably not get that kind of support and spec from cheap Chinese diodes and Ebay items.

Pretty much. If the tube is sealed with all glass seals, or with frit (kind of like solder for glass), it shouldn't leech any gasses at any rate that matters. If it is sealed via a low vapor pressure epoxy or similar, it may or may not lose gasses or leak over time. This is why alot of the old window style Spectra physics lasers no longer work anymore. Helium is a small atom so even if it's well sealed and doesn't leak in contaminates, it may lose helium over the years as the atoms manage to find a way to escape slowly and cause the power to decline, as well as make the tube hard to start. (obviously excluding any physical abuse such misalignment of the mirrors)

Usually when tubes (or really any laser frankly) are made, they have a rated minimum output power, and anything above that is considered acceptable. For example a Spectra Physics model 120 is rated for 5mW @ 7mA upon sale, so at the factory it is guarenteed to do that much at a minimum at that current, but they often do 6 or 7 when they are new. Once the power has declined below that point, it is generally considered to be end of life, but there are exceptions to this rule in some cases.

Most modern professionally made decently sized HeNe tubes are rated for about 10,000 hours of service, but it depends a bit on construction of the tube and the environment it is run in. Many tubes will run for years without issues before they need replacement. It's primarily determined by the amount of available cathode in the tube. It is 'pickled' in an oxide layer of a particular thickness to protect it from the electrical discharge, and after this oxide layer has been spent, the raw aluminum is exposed and will begin to sputter off, which buries gas and plates the tubing and mirrors with the raw vaporized aluminum as it re-deposits, which causes the power to decline and making the power required to run the tube go up, making the tube oscillate and get noisy, which then makes the sputtering worse, etc etc in an endlessly accelerating negative feedback loop until the tube simply exceeds the capabilities of the power supply to run it. It's not entirely dis-similar to fluorescent tube bulbs, which have a similar result at the end of their service life.
 




Top