Talk:TEA laser

Specific notability/merger

Isn't this just a type of nitrogen laser, at atmospheric pressure? Is there any reason not to merge with with the nitrogen laser article (though both need cleaning up, first)? In particular, TEA is really just an excitation geometry, not a disctinct name for the laser - there are TEA CO2 lasers, for instance. --Bob Mellish 16:13, 9 December 2005 (UTC)

Here is an Idea

What do you think about convert the TEA Laser article into the new Nitrogen Laser article, and take some tech data from the oldest one? I think the TEA article have more didactical quality

I think merging this into nitrogen laser would be a good idea. I don't like the fact that the article on TEA lasers doesn't mention TEA CO₂ lasers, which are quite important.--Srleffler 06:25, 13 December 2005 (UTC)

CO₂ do not fit since it is not pulsed. Merging now, clean up later. --Arnero 22:52, 23 December 2005 (UTC)

Possible error in description on this article

The acronym description is incorrect. TEA stands for "Transversely Excited Atmospheric" and it was coined in the early 1970s when we first started working on these types.

Davec13o2 16:58, 25 September 2007 (UTC)

The following page claims that there is no real waveguide in this type of laser. The spark gap is too slow. My calculations confirm that.

http://www.jossresearch.org/lasers/nitrogen/circuitboardlaser.html

Should we fix this article?

Can we fdtd apply here? Runs on Linux and Win, with Source! Instead of the long and questionable text on above link --Arnero 11:18, 15. Apr 2006 (CEST) OK, one would need to add

• a script to generate curved electrodes
• a Poisson equation solver for the initial field, which is then globally scaled up until electric break down
• carrier density. [1]

--Arnero 07:42, 17 April 2006 (UTC)

Already prepared numbers about streamer velocity should be used (1 cm / ns | light= 30 cm / ns): [2], [3], [4], [5], [6], [7], [8] --Arnero 08:42, 23 April 2006 (UTC)

I'm not sure I understand your questions well enough to answer them, but take note of the Wikipedia policy Wikipedia:No original research. The only things that should be included in the article are things that can be found in published references elsewhere. If you do some new calculations or analysis, the results of that are not suitable for inclusion here unless they also appear in the literature.--Srleffler 18:32, 23 April 2006 (UTC)

Possible sources

• how to save search results ?:
  • No simulation: [9]
  • simulation: [10]
  • fast spark gap: A low-inductance, long-life, triggered spark gap switch for Blumlein-driven lasers

T Baby et al 1991 Meas. Sci. Technol. 2 873-875 doi:10.1088/0957-0233/2/9/00

• 38 hits for "nitrogen laser", 24 for "TEA laser" : [11]
• 32 hits on "nitrogen laser", 31 for "TEA laser": [12]

--Arnero 04:54, 24 April 2006 (UTC)

I have no online access to:

Discharge and circuit simulation of a plasma cathode TEA HF laser operating with a He/SF6/C3H8 gas mixture • ARTICLE Pages 145-148 G. N. Tsikrikas and A. A. Serafetinides Optics Communications, 134 (1997) 1-6 , S. 145-8 --Arnero 07:26, 24 April 2006 (UTC)

Spark gap optimization by electrodynamic simulations J Hendriks et al 2006 J. Phys. D: Appl. Phys. 39 274-280 doi:10.1088/0022-3727/39/2/007 Abstract. When switching times are no longer dominated by the plasma formation time, such as for photoconductive switching of high-voltage spark gaps, electrodynamic details of the switching process determine the rise time and pulse shape of the switched pulse. We show that the commonly used zero-dimensional lumped element and one-dimensional transmission line theory are no longer sufficient for optimizing such fast-switching devices, because important electromagnetic-field propagation in three dimensions is neglected. In order to improve the output of the photoconductively switched spark gap, we developed an optimization procedure for spark gap geometries based on full three-dimensional electrodynamic simulations. By monitoring the electromagnetic-field propagation in time, it will be shown that the initial electromagnetic-field disturbance in the gap reflects at the outer conductor and interferes with the initial field. The reflection and interference are essential for the shape of the output signal. We propose the following optimization procedure to improve the output of the photoconductively switched coaxial spark gap. Initially, the reflection and interference can be influenced by reshaping the inner conductor. The outer conductor can be used to fine-tune the system to get an output pulse with a sharp rising edge and no significant oscillations. We also present the optimal spark gap geometry that gives the best output signal at photoconductive switching

Comparison between the discharge development in the two- and three-electrode spark gap switches Hossein Golnabi Results of numerical simulation of two- and three-electrode spark gaps operating with pure nitrogen gas are compared. Our result show that in both cases the discharge process evolves via two stages very similar to that was reported in nitrogen glow discharge studies. First, the primary electrons produce positive nitrogen ions; second, the produced ions can disturb the applied field, and can create the space charge region. The undulations observed are because of the secondary effects, in particular, the cathode-directed streamers. The delay time for the three-electrode spark gap is more than that of the two-electrode discharge. Current growth is faster for the two-electrode spark gap in comparison with the three-electrode one. The oscillations are more enhanced for the case of the three-electrode spark gap. Our simulation method provides both temporal and spatial information concerning the operation of such switches. The reported results are helpful in design and optimization of both the two- and three-electrode spark gaps. ©2000 American Institute of Physics.

A low-inductance, long-life, triggered spark gap switch for Blumlein-driven lasers T Baby et al 1991 Meas. Sci. Technol. 2 873-875 doi:10.1088/0957-0233/2/9/008 Abstract. A low inductance, triggered spark gap switch suitable for a high-current fast discharge system has been developed. The details of the design and fabrication of this pressurized spark gap, which uses only commonly available materials are described. A transverse discharge Blumlein-driven N2 laser incorporating this device gives a peak output power of 700 kW with a FWHM of 3 ns and an efficiency of 0.51%, which is remarkably high for a pulsed nitrogen laser system.

Investigation of the electrical characteristics of charge transfer circuits used in gas laser excitation A D Papadopoulos et al 1991 J. Phys. D: Appl. Phys. 24 1917-1924 doi:10.1088/0022-3727/24/11/004 Abstract. The electrical characteristics of the charge (or capacitor) transfer circuits, which are used for the excitation of pulsed gas lasers, are investigated. The formalism that is followed is based on the solution of the differential equations that are obeyed by the currents that flow in the two loops of the circuit. The theoretical predictions are confirmed by experimental data taken with a nitrogen laser. The method can be applied to any type of gas laser using a charge transfer circuit, so that the shape of the voltage and current waveforms can be predicted from the circuit parameters and vice versa. Two other important parameters, the resistance and inductance of the discharge plasma, can also be found.

A nitrogen laser excited by a nanosecond microwave discharge A L Vikharev, A M Gorbachev, O A Ivanov, L S Ivanova and A L Kolysko Inst. of Appl. Phys., Acad. of Sci., Nizhny Novgorod, Russia Abstract. Experimental results on excitation of a nitrogen laser by means of a nanosecond microwave discharge in a wave beam are presented. The possibility of producing an atmosphere laser with remote microwave pumping is demonstrated. The numerical model for the nitrogen laser excited by a nanosecond discharge in a cylindrical TE wave in a tube and in free space is constructed. It is shown that, by changing the pressure of the laser mixture, the diameter of the gas discharge tube and the value of incident microwave power one can efficiently control the discharge parameters and achieve total absorption of microwave radiation and high efficiency of laser generation

The design and coherence properties of a simple N2 laser O Steinvall et al 1973 J. Phys. E: Sci. Instrum. 6 1125-1128 doi:10.1088/0022-3735/6/11/024 Res. Inst. Nat. Defence, Stockholm, Sweden Abstract. A compact electrical pulse circuit suitable for exciting pulsed gas lasers has been developed. The advantages are the low input voltage (10-20 kV) and the possibility of an output voltage of more than 100 kV. The rise time was found to be less than 10 ns. The design is described and has been used to excite a nitrogen laser. A maximum output power of 500 kW (pulselength 5 ns) with a repetition rate of 1 Hz was achieved from a 36 cm long tube, 6 mm diameter. When the repetition rate was 100 Hz the output power was about 50 kW. The spatial and temporal coherence was also studied. It was found that the spatial coherence existed over the whole cross section of the beam. By operating the laser below the saturation level and introducing mirrors the pulse length could be changed in the range 4-10 ns. The time coherence was approximately equal to the halfwidth of pulse. The beam divergence was improved by a factor of 1o by using a complete cavity instead of a single rear mirror.

Nitrogen laser with high pulse and average power V Serbezov et al 1990 Meas. Sci. Technol. 1 601-604 doi:10.1088/0957-0233/1/7/010 Abstract. A description of a nitrogen laser, transversely excited by a double Blumlein line with automatic corona preionisation is given. The preionisation capacitor is formed by the dielectric material of the laser chamber. The discharge volume is 77.4 cm3. The achieved energy per pulse and average power were Ep=10 mJ and Pm=600 mW when preionisation was used. without using preionisation these values were Ep=7 mJ and Pm=270 mW respectively. The effect of corona preionisation upon the energy and frequency characteristics of the laser was studied

High power N2 laser with a modified gas flow system and discharge geometry Thomas Baby, T. Ramachandran, K. Sathianandan, V. P. N. Nampoori, and C. P. G. Vallabhan A high power N2 laser of the double-Blumlein type having a modified gas flow system, electrode configuration, and discharge geometry with minimum inductance is described. By incorporating a triggered-pressurized spark gap switch, arc-free operation was achieved for a wide E/P range. The device gives a peak power in excess of 700 kW with a FWHM of 3 ns and an efficiency of 0.51%, which is remarkably high for a pulsed nitrogen laser system. The dependence of output power on parameters such as operating pressure, voltage, and repetition rate are discussed. Review of Scientific Instruments is copyrighted by The American Institute of Physics

New model for ultracompact coaxial Marx pulse generator simulations Benoît Martin, Pierre Raymond, and Joseph Wey This article describes a new simulation model developed with PSPICE in order to improve the ultra compact Marx generators designed at the French-German Research Institute of Saint-Louis (ISL). The proposed model is based on a Marx elementary unit and is an equivalent electric circuit that matches the actual configuration of the generator. It consists of a structural description of the elementary stage of a Marx generator including stray components. It also includes a behavioral model of the spark gap switches based on the Vlastos formula determining the arc resistance value. The prebreakdown delay is also taken into account. Experimental data have been used to validate the results of the simulations. An original indirect measurement, allowing the estimation of the spark gap resistance, is also proposed. ©2006 American Institute of Physics

Novel multiple-switch Blumlein generator Z. Liu, K. Yan, G. J. J. Winands, E. J. M. Van Heesch, and A. J. M. Pemen The Blumlein generator has been one of the most popular pulsed-power circuits. The pulse forming lines are charged simultaneously, and then discharged via a single switch, such as a spark gap. The generator can be used for single pulse or at a high repletion rate. However, for large pulsed power generation, one critical issue for such a single-switch based circuit topology is related to large switching currents. In this article, we propose a novel Blumlein circuit topology based on multiple switches. The pulsed forming lines are charged in parallel and then are synchronously commutated via multiple switches. No special synchronization trigger circuit is needed for the proposed circuit topology; this robust circuit topology is simple and very reliable. A prototype multiple-switch Blumlein generator with two spark-gap switches has been experimentally evaluated with both resistive and corona plasma loads. In terms of the switching currents, it is observed that the two switches can be synchronized within 2–3 ns. The energy conversion efficiencies are 82% and 76.8% for a matched resistive load and a plasma reactor, respectively. ©2006 American Institute of Physics

Synchronization of multiple spark-gap switches by a transmission line transformer Z. Liu, K. Yan, A. J. M. Pemen, G. J. J. Winands, and E. J. M. Van Heesch A transmission line transformer (TLT)-based multiple-switch circuit topology was recently proposed for pulsed-power generation. By means of a TLT, multiple spark-gap switches can be synchronized in a short time (ns). It is attractive to be used to design a long-lifetime repetitive large pulsed-power source (100 kW, 1 kHz) for various kinds of applications, such as corona plasma-induced gas cleaning. To gain insight into the synchronization principle and switching behavior of the individual switch, an equivalent circuit model was developed and an experimental setup with two spark-gap switches and a two-stage TLT has been constructed. We observed that in terms of switching currents, the two switches can be synchronized within 2–3 ns. The equivalent circuit model approximately fits the experimental results

Dielectrics for corona preionisation of a TEA laser B Walter 1985 J. Phys. E: Sci. Instrum. 18 279-281 doi:10.1088/0022-3735/18/4/006 B Walter TEch. Univ. Wien, Austria Abstract. A small TEA CO2 laser was built to investigate the relative effectiveness of a corona discharge as a preioniser. Macor, pyrex glass, pertinax, epoxy and acrylic plates were used as dielectric material, and their influence on the performance of the laser discharge was investigated. It is shown that the dielectric determines the amount of energy that can be deposited in the gas prior to arc formation, and the laser output energy. Macor was found to be superior to all other dielectrics in this regard.

Corona-preionized nitrogen laser with variable pulse width Laser Physics Center, AEOI, P. O. Box 11365-8486, Tehran, Iran A simple method of producing pulsed coherent radiation at 337.1 nm with variable pulse durations of 2.0–3.5 ns using a small transversely excited N2 laser is described. For laser operation in a moderately broad range of gas pressure (up to 1 atm), a weak surface corona discharge has been utilized as a preionizer. The electrical excitation is a flat plate Blumlein circuit with the main electrodes fixed at a height of 35 mm above the corona streamers. The laser produces an output peak power in excess of 70 kW at 350 Torr gas pressure and pulse repetition rate of 10–50 Hz. Review of Scientific Instruments is copyrighted by The American Institute of Physics

A small rugged nitrogen laser for instrumentation Silvana Vianna Rodrigues and Wolfram Baumann A novel small and rugged type of a free running atmospheric pressure nitrogen laser is presented and its behavior is studied in detail. Pulse half-widths are between 800 ps for 60 mm active channel length, and 1.1 ns with pulse energies of 150 µJ for 170 mm active length, both at 2.4 mm laser gap. The maximum pulse energy is found at a field strength-to-pressure ratio around 110 V/(cm Torr), in agreement with what is reported in literature for nitrogen lasers. Preionization by ultraviolet light from the free running spark gap could be ruled out while corona discharge over the capacitor foil surface between the laser electrodes could not be excluded. Review of Scientific Instruments is copyrighted by The American Institute of Physics.

Reliable spark gap switch for laser triggering Hossein Golnabi The design of a low inductance spark gap suitable for triggering lasers, using circuit boards as transmission lines, is presented. This spark gap is highly reliable for repetitive switching, and it is capable of delivering high voltage and current in the triggering operation. The switch performance has been studied in a nitrogen laser driven by a Blumlein circuit, and the preliminary results are reported. When operated at a rate of 10 pps the switch provided reproducible pulse waveforms without maintenance for a total of 108 laser shots. Review of Scientific Instruments is copyrighted by The American Institute of Physics.

Ultraminiature high-power gas discharge lasers excited through high dielectric constant ceramic materials National Physical Research Laboratory, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria, Republic of South Africa The authors show that millimeter-size high-pressure UV nitrogen lasers can be excited through high dielectric constant materials and provide peak beam powers of 104–105 W. Review of Scientific Instruments is copyrighted by The American Institute of Physics.

Novel discharge circuit for a multijoule TEA CO2 laser Department of Physics, Heriot–Watt University, Edinburgh EH14 4AS, United Kingdom A novel discharge circuit that reduces significantly the amount of energy conducted by the switch in a TEA CO2 laser is reported. We demonstrate this circuit on a working multijoule TEA CO2 laser in which the switch is shown to conduct typically only 5% of the total input pulse energy. The laser has worked reliably in gas mixtures that place stringent demands on the discharge and circuit. It has produced an output of 7 J at an efficiency of 9.6% using a CO2:N2:He (1:1:4) gas mixture at atmospheric pressure and further using a helium-free gas mixture (CO2:N2:H2 at 400 mbar) it has produced a maximum efficiency of 14.6% for an output of 7.8 J. The great simplicity and high efficiency of the new discharge circuit allow it to be incorporated in the existing laser designs with minimal modifications. Review of Scientific Instruments is copyrighted by The American Institute of Physics.

High Trigger Current Structure for Double-Discharge TEA Lasers G. Otis The use of resistive plastic materials in the trigger circuit of double-discharge lasers has proven excellent in producing increased trigger current values, and in achieving successfull operation of lasers with large (up to 7.6 cm) electrode separations. Small signal gain values of 0.04 cm–1 have been obtained in a He:N2:CO2=50:20:30 gas mixture. Furthermore, the dielectric constant and resistivity of the plastic materials can be selected for pulse shaping in the trigger circuit. A trigger assembly has been designed in a simple and rugged unit, suitable for cascaded operation in long laser amplifier systems. ©1972 The American Institute of Physics

Miniature TEA N2 laser with automatically timed UV preionization H. Houtman and J. Meyer A novel modification to the Blumlein circuit excitation method is presented which allows for automatically timed UV preionization of the main-glow discharge of a miniature 337-nm N2 TEA laser without the use of time-delayed circuits commonly used in larger transverse discharge lasers. The laser reliably produces subnanosecond, gain-switched output pulses of 65 kW at rates up to 50 Hz, with a stability of a few percent, and efficiency of 0.06%. Review of Scientific Instruments is copyrighted by The American Institute of Physics

A practical design of a nitrogen laser A J Schmidt 1977 J. Phys. E: Sci. Instrum. 10 453-455 doi:10.1088/0022-3735/10/5/011 Inst. fur Phys. Elektronik, Tech. Univ. Vienna, Vienna, Austria Abstract. A practical design and the construction of a high-power nitrogen laser are described. It delivers pulses of up to 3.5 mJ at a rate of 10 per second. To optimize its performance as a pump source for a Hansch-type dye laser, a comparatively long pulse width (about 10 ns) has been chosen. Special care has been taken to make maintenance as convenient as possible. The fast transmission line is formed by sheet capacitors, which are held together by atmospheric pressure only and are therefore easily demountable in the case of dielectric breakdown.

Sealed-off, miniature, high-power nitrogen laser H M von Bergmann 1977 J. Phys. E: Sci. Instrum. 10 1210-1212 doi:10.1088/0022-3735/10/12/002 H M von Bergmann Optical Sci. Div., NPRL, CSIR, Pretoria, South Africa Abstract. By the use of ceramic-to-metal high-vacuum sealing technology, a sealed-off, miniature, high-power nitrogen laser operating at 337.1 nm has been constructed. The laser is excited transversely by a fast Blumlein pulser and uses UV photoionisation stabilisation. Peak output powers exceed 150 kW with pulse lengths ranging from 0.3 to 1 ns. No deterioration of the output was observed over more than 108 shots.

TEA laser gas mixture optimization W. Michael Lipchak and Clarence F. Luck The topographical plot of an optimized parameter, such as pulse energy or peak power, on the gas mixture plane is presented as a useful aid in realizing optimum mixtures of helium, carbon dioxide, and nitrogen, for operation of CO2 TEA lasers. A method for generating such a plot is discussed and an example is shown. The potential benefits of this graphical technique are also discussed. Review of Scientific Instruments is copyrighted by The American Institute of Physics.

Multichannel surface arc switch D. B. Cohn and E. E. Conley A simple, multichannel surface switch has been developed suitable for pulse generators commonly used for TEA laser excitation. Switch voltages over the range 15–35 kV were successfully tested. Low energy, auxiliary discharge triggering was found to increase arc channel number density under some circumstances. Review of Scientific Instruments is copyrighted by The American Institute of Physics

Efficacy of laser preionisation with a semiconductor source and propene addition S J Scott et al 1984 J. Phys. E: Sci. Instrum. 17 1242-1243 doi:10.1088/0022-3735/17/12/036 S J Scott and A L S Smith BAe, Sowerby Res. Centre, Bristol, UK Abstract. It is established that propene is an effective additive in stabilising UV preionised CO2 TEA laser discharges. Its effect is particularly pronounced with semiconductor-edge preionised lasers where the preionisation levels are shown to be low.

An ultraviolet preionized nitrogen laser switched by parallel spark gaps H K Law, W O Siew, K K Tham and T Y Tou Institute of Advanced Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia Abstract. We present a simple method of switching a nitrogen laser with three parallel, self-breakdown spark gaps by incorporating them into a two-stage Blumlein circuit. These spark gaps are preionized by ultraviolet radiation from an auxiliary spark which suppresses their breakdown jitters and improves their temporal sychronization. The breakdown time delay of these parallel spark gaps enables strong ultraviolet preionization of the laser channel. As a result of these improvements, the laser output is doubled and is more reproducible than that obtained using the one-stage Blumlein circuit.

An inexpensive TEA N2 laser as a pump for a dye laser amplifier system G Veith et al 1978 J. Phys. E: Sci. Instrum. 11 833-835 doi:10.1088/0022-3735/11/8/031 Abstract. A simple design for a transversely excited atmospheric pressure (TEA) nitrogen laser capable of repetition rates up to 100 Hz is described. Commercial-grade N2 is blown through the open laser channel so that no vacuum system is necessary. Without any mirror the laser provides UV outputs ( lambda =337.1 nm) at both laser ends with a total average power of up to 23 mW. Using one of them to pump a Hansch-type dye laser and the other to synchronously pump an amplifier we obtain, with rhodamine 6G as the lasing dye, tunable pulses with an energy of approximately 1 mu J and a bandwidth of less than 0.07 nm.

MOSFET trigger circuit for grounded grid thyratrons R Bayerer et al 1983 J. Phys. E: Sci. Instrum. 16 1148-1149 doi:10.1088/0022-3735/16/12/004 Abstract. A trigger circuit on the basis of 'Vertical' MOSFETs is described. It gives a 1.5 kV voltage step with 15 ns risetime at the cathode of a EG&G grounded grid thyratron. The thyratron is incorporated in a transverse-discharge nitrogen laser. The jitter in laser pulse emission, i.e. thyratron firing, is restricted to less than 1 ns.

--Arnero 21:22, 25 April 2006 (UTC)

Proposed Rewrite

This article is very sloppily written. Apart from the basic fact that the meaning of “TEA” is incorrectly stated – as already observed above – the scope and focus of the piece is entirely inappropriate, and there is no historical background. I propose to completely rewrite the article, but since my knowledge is somewhat out of date – I built TEA lasers in the early 1970s at Essex University in England – I invite other Wikipedians to comment and correct as they see fit. I would also welcome some encouragement in this: do other contributors/readers find this article as bad as I do? Peter Maggs (talk) 13:14, 4 January 2008 (UTC)

Definitely, I think it reads more like an argument at the moment. It only really makes sense if you already know the subject matter, which isn't a good way to be; I was hoping for enough background to be able to build one but I don't think that's likely now! Stonejag (talk) 09:28, 6 January 2008 (UTC)

I have rewritten this article based on what I know. Whether or not the Nitrogen laser is a true TEA laser - in the sense that I understand the term - is a moot point. I invite others with more up to date knowledge than mine to clarify this point, perhaps expand the part on Excimer Lasers and ensure that the article measures up to the subject. Peter Maggs (talk) 13:38, 6 April 2008 (UTC)

20080420 revision critics

there was a big revision towards readability. Things are lost:

• Links to other wiki articles (for example Carbon dioxide laser)
• Other laser types then CO2
• high frequency electronics
  • CO2 has 4 states, so speed is no problem. The last editor apparently does not know N2, H2 lasers
• the thyratron is not responsible for high rep rate, but low jitter

Arnero (talk) 06:35, 21 April 2008 (UTC)

Links need to be restored; I will restore some and leave others to the more eagle-eyed of my colleagues. The point about speed - if I have understood the comment - is not about the CO2 laser process itself but the gas-discharge that puts energy into the gas. Unless the discharge is fast, it breaks down into high-current arcs useless for energising the nitrogen and CO2. I am aware of nitrogen lasers, and I have already commented that I am not sure whether the nitrogen laser is what I would call a TEA laser.Arnero, You are not correct about the thyratron. Thyratrons do provide very low jitter but for continuous high repetition rates with affordable switch lifetimes, only thyratrons or complex and expensive solid-state/magnetic switch combinations can be used, and the thyratron is generally easier to engineer and cheaper. Peter Maggs (talk) 15:06, 21 April 2008 (UTC)

thyratron

I agree. I have not compared lifetimes. Maintenance is surely also important.

arcs

The discharge minimizes energy-loss due to thermal radiation. Is there any scaling law for pressure, current, diffusion length, and laser volume needed for homogeneous discharge ?

Nitrogen

It runs with air and it is transversal excited. Of course 1/10 atmospheric pressure works much smoother, but the construction remains the same.

Arnero (talk) 21:12, 2 May 2008 (UTC)

Subtle vandalism?

"Pearson and Lamberton used a streak-camera to verify the sequence of events. As the voltage erected across the electrodes, field emission from the..."

This looks like vandalism to me, but I am not familiar with engineering jargon, so I haven't edited the article. However, in my opinion, the verb should still be changed to "increased" or somesuch, even if some proffesionals do use the above expression, simply because "erected" would be perceived as informal or dirty to the majority of readers.82.137.34.99 (talk) 17:38, 20 July 2008 (UTC)

I wrote the article. Talking about voltages "Erecting" is perfectly normal in pulse-power speak. Peter Maggs (talk) 21:40, 20 July 2008. Of course it has only just occurred to me that the post from 82.137.34.99 was a joke. If so, the joke's on me. Peter Maggs (talk) 17:33, 21 July 2008 (UTC)(UTC)

Sociology of scientific knowledge

The development of this laser was examined by Harry Collins in "The TEA set: Tacit knowledge and Scientific Networks". Science studies 4, 1974 p165-186. A mention would be good. — Preceding unsigned comment added by Smartse (talk • contribs) 21:34, 22 April 2009‎ (UTC)

I added a brief section in the article on Collins’ work. Simulo (talk) 17:13, 31 October 2023 (UTC)

Fraudulent external link?

The linked page [Simple Homemade T.E.A. Laser] looks totally fraudulent to me. The author appears to just create a spark between two strips of metal that happen to direct the light along their length, then claims it's a laser. There isn't even a mirror. Can this link be deleted? Gareth.randall (talk) 11:37, 28 December 2009 (UTC)

Problems with the April 2008 rewrite - style & tone

Since the April 2008 revisions mentioned above, the article has lost

• the lead section
• the expansion of the acronym (it's buried in the 4th paragraph)
• a lot of the diagrams
• structure (it is now one large block of text)

Most critically, the tone has shifted significantly; there's a lot of focus on the history and not that much on the theory and operation. The March 2008 version is vastly superior to the current article. 115.166.3.252 (talk) 14:36, 14 September 2010 (UTC)

The April 2008 Rewrite

It is a pity that ‘115.166.3.252’, 14 September 2010 – which I have only just seen – comments anonymously. My criticism of the original article is even more reinforced having re-read the so-called ‘vastly superior’ March 2008 version. The writers of that version are clearly very knowledgeable about some parts of laser technology, but time and time again they mistake the specific for the general. Most TEA lasers just do not use the type of electrical excitation structure described, which seems to relate more to nitrogen lasers and experimental excimer lasers. The provision of nice coloured diagrams and lots of sections does not justify the presence of much material that is simply irrelevant.

I only replaced the existing article following a post on the talk page encouraging me to do so. Granted, the new article relates mainly to the historical evolution of TEA lasers, I make no apology for that because surely the topic demands to be put into a historical context in an encyclopaedia. In my various posts I have encouraged other Wikipedians to amend and add to my original rewrite, since my knowledge of the subject is at least 20 years old. It is a great pity that hardly anyone has done so.

I propose to remove the ‘inappropriate tone or style’ banner from the article, subject to the views of other Wikipedians who may care to comment. Peter Maggs (talk) 10:35, 13 April 2011 (UTC)

There have been no comments since my last post, so I have made the changes proposed, modifying the text also. The scope of the article does need to be increased, and up to date information on TEA lasers added. Peter Maggs (talk) 10:30, 18 April 2011 (UTC)