(The following photo provided courtesy of: CTR Surplus.)
(The following photo provided courtesy of: Donald Long (donlong@involved.com).)
(The following photo provided courtesy of: simba6 (ampartes@megsinet.net).)
(The following photo provided courtesy of: James Purrington (jppurrin@mtu.edu).)
This is a rather old Spectra-Physics two-Brewster HeNe laser tube, used in the SP-119 stabilized HeNe laser. (More information including photos of the SP-119 can be found in Sam's Laser FAQ Chapter: Commercial HeNe Lasers. The overall design is similar to many other SP tubes including the one in the SP-130 laser, but it has a really large gas reservoir and extended glasswork. Perhaps this was before the SP engineers realized that the He and Ne atoms would cooperate and fit into smaller spaces. :) But more likely, the extended glasswork was required to be able to mount the actual bore with the Brewster windows inside a heater jacket. And the large gas reservoir was provided to maximize life as stabilized lasers are often run continuously for years.
(The following 4 photos provided courtesy of: Mike Kenny (MKenny1989@aol.com).)
This is a soft-sealed tube of rather conventional design except that the bore is stepped in at least 2, possibly 3 places. The cavity is close to hemispheric. So, instead of tapering the bore which would probably be more difficult and expensive, this approximately matches the mode volume to the bore. At the cathode/HR-end, the bore is narrow, a millimeter or maybe even less. There may be a step in the bore inside the cathode where it isn't visible. Then, just beyond the end of the cathode cylinder, there is a step increasing the bore diameter to perhaps 2 mm as shown in the View 4, and another one just to the right of the getter spot (not shown) increasing the bore diameter to 3 or 4 mm from there to the anode/OC-end.
This sample still has a healthy-looking discharge color with an output of around 0.5 mW at 6 mA. The beam diameter at the OC is probably over 2 mm but just a pin-point at the HR. I do not know what the reated power was but although the tube is over 12 inches long, with the wide bore for over half its length, it couldn't have been as high as it would be for a similar length modern tube, possibly 2 or 3 mW. If anyone has more information, please send me Mail.
(The following photo montage and description provided courtesy of: Ron Soyland (ronsoy@earthlink.net).)
Well, as far as lasers go it's antique! This is one of the first helium-neon lasers available on the market! It is a Spectra-Physics model 110 made back in the 70's when lasers were thought to be dangerous death rays! (I think this was actually more like 1963 or earlier. --- Sam.) This one has an open cavity construction and had an output power that could exceed 15 mw with careful adjustment of the mirrors. This laser uses RF excitation so that there was no electrodes inside the tube. This allowed the testing of gases that would attack metals. This particular laser was used in a laboratory that was investigating different gas mixtures and laser wavelengths. A filling tube has been fused to the plasma tube so it could be attached to a vacuum system and gas charging system. The laser is not in operating condition as it sits because the valve on the filling tube leaks down gradually. The discharge in the pic is from a charge of helium that was put in the tube to test the power supply and oscillator to make sure it still works. Note that to make this laser actually lase, would require access to a vacuum system and proper gas charging system.
(The other three photos and following description is from Bob Hess.)
I bought this Perkin Elmer/Spectra-Physics Model 110 HeNe laser from Ron Soyland. The SP-110 was the first CW commercial laser made with a visible beam. The Model 100 was the first commercial CW laser, but it was IR. The first 75 lasers made by Spectra-Physics also carried the Perkin Elmer name. The only other Model 110 I know of is in a display at Spectra Physics. Mine is missing its cylindrical end covers, a power supply and its boots.
Ron Soyland had a gas fill valve installed which required the moving of one of the end-plates of the central housing to the outside of the housing, and the drilling of a hole in the front face (which I plugged). It's interesting to see the evolution of these lasers. Look at how the tube length grows, the mirror mounts change and better adjusters are added as they went through the series of Models 110, 111, 112, and 113.
(The following photos provided courtesy of: Robert A. Hess.)
I acquired this laser head 20+ years ago, from a Silicon Valley dumpster-diver, for $200. He needed the cash to get out of jail. It's missing the HR, and there may have been end covers because there appear to be attachment provisions for them. The getter in the tube is intact. I've never even touched the tube with a Tesla coil (don't have one now). I always thought the tube was old. After reading the history of holography and the laser, I've learned that the Model 111 was a run of only 75 lasers produced for Perkin Elmer within 18 months in 1962 and 1963.
This is a very old laser which appears to be the big brother or father of the SP-115. It is about 5 feet long and also RF excited. I don't know what specific exciter is used but it may be the SP-200 or something larger.
Like the SP-115, the SP-112 has a tube with a large gas reservoir in a side-arm, RF and starting electrodes, and micrometer adjustments for the resonator.
(The following photos provided courtesy of: Ed Kirby (edkcpb@yahoo.com).)
(The following 4 photos and parts of description provided courtesy of: Orey Block (orey@worldnet.att.net).)
Here is a very old laser, probably from the 60s, latest early 70s. It is RF excited and a nice example of original HeNe technology. The tube is over a foot and a half long with separate bore and gas chambers and is wonderfully mounted with lots of nice machined hardware. It has two RF connectors on the side for the Spectra-Physics model 200 RF-type power supply. An impedance matching network located under the "tube deck" drives a dozen or so electrodes with alternating polarities in proximity to the tube bore. The laser has externally adjustable mirrors, which are truly separate from the tube and joined by removable rubber bellows exposing the Brewster windows. The front mirror has fine adjustments in X and Y via two precision Lufkin micrometers and the rear has a micrometer adjustment for mirror separation (try to find that on any modern laser!).
Here are some photos of the SP-200 Exciter. All active elements are tubes, of course. :) It is a high quality 15 to 25 watt 40.68 MHz RF source consisting of a crystal controlled oscillator and a power amplifier using a 4x150.
This is a small "Stabilite" laboratory laser with its separate exciter. The minimum guaranteed output power of the SP-120S laser is 6 mW (red, 632.8 nm) though quite a bit more may be possible when new.
(The following photo provided courtesy of: Edward Roth (edjroth@msn.com).)
This is either the guts of a SP-120 laser head or the OEM version of the SP-120 where the laser is installed in someone else's equipment. The L-shaped frame is very stable though the HeNe tube itself is just suspended by an O-ring cushioned holder at each end. These can be adjusted slightly in 2 dimensions (pan and tilt) to center the tube, which also provides fine mirror alignment. Coarse mirror alignment is via mounts with three hex-head screws. I don't know the age of this particular laser but with some tweaking of the mirrors, I was able to get over 7 mW out of it - better than the new specs! Note that the bracket which sets the angular position (to align the polarization orientation and stabilize the tube against mechanical shock) is missing (reason unknown). This would be visible in View 08, clamped to stainless steel Brewster cover and cathode stem. the
(The following 3 photos and description provided courtesy of: Orey Block (orey@worldnet.att.net).)
This is an early Stabilite style laser. It appears to be about 2/3rds of the length of an SP-124 so its output power was probably between that of the SP-120 and SP-124 - perhaps 10 mW or so. The power supply is internal.
This is the very popular SP-124A "Stabilite" laboratory laser with its SP-255 Exciter. I don't have specs on the expected power output of this model. The minimum guaranteed output power of the SP-124B is 15 mW (red, 632.8 nm) though 25 mW or more may be possible when new. (IR models are also available: option -01 for 1,152 nm, 2 mW; -02 for 3,391 nm, 5 mW.) I also don't know what differences exist between the SP-124/A/B lasers. They appear to be virtually identical physically. If anyone has more information, please send me Mail.
The interior construction of this laser head is quite similar to that of the slightly larger (30 mW) Spectra-Physics HeNe model shown above.
(The following 3 photos provided courtesy of: Bob Lachata (ldesign@theramp.net).)
This is without doubt one of the largest HeNe laser models ever built. The head alone is over 6 feet long and weighs more than 100 pounds. When new, some of these output as much as 200 mW at 632.8 nm. Optics sets for other wavelengths are/were available.
(The following 2 photos provided courtesy of: Edward Roth (edjroth@msn.com).)
(The following 4 photos provided courtesy of: Ryan (ryanh@cogeco.ca).)
This is also a rather large HeNe laser but not nearly the size of the SP-125. It is self contained with an internal brick type power supply. Rated output power is around 35 mW (CDRH max: 60 mW). The beam cuts through T-120 video tape like butter when focused. Dimensions are: 42-1/2"(L), 5-7/8"(W), 4-9/16"(H) including foot projection. Weight is approximately 20 lbs.
(The following photos provided courtesy of: Dave (Ws407c@aol.com).)
This is probably one of the earliest self contained portable HeNe lasers ever sold. My original "Model 130 Gas Laser Operation and Maintenance Manual" has diagrams with dates as far back as 1965! It even has a genuine leather carrying handle. :) The overall construction is superb using precision machined anodized aluminum for the main structure as well as the covers - built more like a Sherman tank than a laser.
The SP-130B uses a HeNe tube with Brewster windows and external mirrors all in a self contained box. The laser is cute - about 13.5"(L) x 4"(W) x 5"(H) and weighs about 11 pounds (most of the weight being the brute force power supply, chassis, and covers. Well, what else is there?)! Unfortunately, the tube died since the second photo was taken due to unknown (but natural) causes. It would appear that the stress of the thermal expansion of one of the seals after being idle all these years caused it to open up after a few minutes of operation (though the tube had leaked somewhat as well and there was no beam even while there was a discharge glow). I have not yet found the seal problem though. The tube in the other sample was totally dead - up to air showing signs of previous attempts at repair.
However, I have since obtained a third SP-130B which originally had a red/blue discharge. But while running for a few hours, the color gradually changed to a mostly correct white-ish red-orange. And, with an optics cleaning and alignment, this SP-130B actually lases. The output power is not up to spec - about 0.25 mW at maximum current (it's rated at 0.75 mW) - but that's still a bit amazing considering its age.
(The following photo provided courtesy of Gary Hansen (gary@astro.as.utexas.edu).)
The SP-132 uses a doubler for the operating voltage and a 3 stage multiplier for the starting voltage with a large (272K) ballast resistance to provide some stability. This is closer to the SP-130 design than the SP-155, which uses a linear regulator.
(The following photo provided courtesy of: simba6 (ampartes@megsinet.net).)
Here are photos of another version of an SP-132, perhaps one that is newer or older or something. :) Both the case and tube are slightly different. With the longer active discharge length, the output power is probably higher.
(The following 3 photos provided courtesy of: Mark Buckles (markbkls@cts.com).)
This is yet another small Spectra-Physics laser but constructed as a compact laser head and separate exciter. The tube looks similar to the other older internal mirror tubes with soft-seal construction. In fact, it appears virtually identical to the tube in the SP-132 laser (above) except that the anode connection is made through the glass in a position resulting in about twice the active bore length (near the clip at the other end of the capillary). Though the discharge color is slightly pink/white indicating slight air leakage, there is still an output of about 0.4 mW (probably should be 2 mW or so). I will need to fire the getter if just running it for a few hours or days doesn't help.
(The following photo provided courtesy of: Mark Buckles (markbkls@cts.com).)
The SP-155 is the basic bare bones HeNe laser no doubt used for all sorts of educational applications. It's self-contained, fairly robust, and low enough power to be almost totally safe.
This laser uses a tube nearly identical to the SP-076-4 shown above. However, note that the distance from the anode lead to the cathode side-arm is less than half the total length of the tube. The power output is listed as 0.5 mW. I wonder if Spectra-Physics had a standard model 'small HeNe tube' and customized its output power by the placement of the anode. :) This would result in lasers with the same mode spacing, beam divergence, and stability characteristics. If anyone has a more reasonable explanation, I would like to hear it! (One sample of the SP-155 I have looks exactly like these photos but is tired - 0.3 mW max without trying any rejuvenation as yet.) Another one into which I installed an apparently never used tube does 0.65 mW.
Although the HeNe tubes for the SP-132 and SP-155 are similar, the SP-155 uses a somewhat lower output voltages but includes a linear regulator.
And, there are modern versions of the SP-155 though I don't know if they still use a side-arm tube or have converted to the more conventional design. There are also lasers which which look the same from other manufacturers that definitely use modern style HeNe barcode scanner tubes.
(The following 3 photos provided courtesy of: Chris Harriman (chrish@netmedia.com).)