• Laser Innovations
  • The top reasons why you should buy a Solid State laser system from Laser Innovations.
• DPSS
  • The top reasons why you should NOT buy a DPSS laser system.
• Pictorial Comparison

The top reasons why you should buy a 
Solid State laser system from Laser Innovations.

1. The IR laser diodes are located in the power supply.
   • Diodes are a consumable item, these can be replaced in the field in about 24 hours.
   • Diodes are a source of heat, this heat is removed without effecting the performance of the laser system. 
   • Upon diode failure, a simple phone call can be made, and a replacement
     diode will be "Fed-X'd" to your site. Down time is NOT an issue. 
2. The doubling and tripling crystals:
   • The doubling and tripling crystals degrade with hours of use, these are field serviceable, and down time is NOT an issue.
   • Translating the crystals, in the field, after degradation will NOT cause the laser cavity to mis-align. Re-alignment of SLA optics is NOT required. 
3. The pulse width of the Laser Innovations lasers are 10 nsec.
   • Shorter pulse widths result in much higher pulse peak powers. Much lower average power is incident on the doubling and tripling crystals, resulting in longer crystal lifetimes. 
4. Solid state resin
   • The solid state resins were developed & characterized with a (10 nsec / 22khz / 400Mw) specific peak pulse power of 1820 Watts (the same laser as Laser Innovations')
5. IR modulator - standard 
   • This allows for accurate power control, via existing buildstation software.
   • The doubling and tripling crystals will be exposed to lower IR power levels, which will result in longer lifetimes.
6. The laser system is not water-cooled. 
7. The Laser Innovations laser uses the internal A/O modulator 
   • This A/O modulator was designed to be used with a PULSED Solid state laser. 
     Accuracy will NOT be effected, and performance will be enhanced.
   • Resin (vat lifetime) will last longer.
   • This optical element proves to be a 0% loss in power to the vat.
   • Our internal IR AOM has an extinction ratio of 200:1, or greater. (1mW at the vat for every 200mW of power from the laser.
8. Laser system is controlled through the same buildstation software operation, as the Argon ion laser system. (Specifically designed for this OEM application.)
9. Reliability issues. 
   • Less than 2%, there are over 400 of these Solid state laser systems in use.
10. The laser system CAN BE repaired "on-site" - it does NOT have to be shipped back to the factory, on a "swap-out" basis for diode replacement, or any other components.
11. Remote control of power, or any other parameters from the laser. External display provided to the user; verify the power, rep-rate, or any other diagnostic status of the laser.
12. These laser systems are UL-listed, & CE certified - most insurance companies require
    this for their policy. This Laser will NOT drop in power when the SLA-500 system goes through the normal "laser ON" and "laser OFF" build cycle of the machine. That is why we designed the software to be compatible with that of the buildstation software, which then can be used with "smart power". 
    The software on the machine was originally designed for optimal laser life, for the Argon laser. When the build was complete, the machine would turn the laser system "Off", saving hours of valuable laser life until the next build was started. This would increase the laser lifetime, and as a bonus; show the depreciation of the laser replacement cost (in hours) over the actual build time (in hours), to the accountants - as a direct comparison. We saw no reason to change this style of operation, only to benefit from it.
    
    Laser Innovations - The company, & some history
13. Started in Feb of 1988, as a Coherent Ion laser remanufacturing facility. LI offered complete system sales, service & support of these water-cooled laser systems.
14. Total number of employees 7 + 5 FE's for stereolithography.
15. Facility is ~ 10,000 square feet.
16. Presently is 13 years old, and… 
    • Since Founded in 1988, the company's two original co-founders are still here. 
17. More than 15 years experience in field service, & OEM customer support. (8 years in this market.)
18. We do provide a trade-in credit, or will purchase
    • your Coherent Argon Ion laser system, from your SLA-500. 
    • your Omnichrome, or Liconix HeCd laser system, from your SLA-250

    Spectra-Physics - The company, & some history (ISO-9000 certified)

19. Started in 1966, as a Manufacturer of Ion laser technology, has grown to become the largest Manufacturer in the world of Solid State laser systems. 
20. Total number of employees ~2,000 
21. Presently is 34 years old.
22. More than 30 years experience in field service, or OEM customer support. (11 years in this SLA market.)
23. Currently 3D Systems buys the Spectra-Physics solid state laser for their SLA-350, SLA-3500, SLA-5000, and SLA-7000 machines.
24. Pricing is very stable.
25. All key internal laser components are manufactured by SP, or by their subsidiary companies.
26. The company is ISO-9000 certified.

  Pictorial Comparison of Laser Innovations' laser system 
VS. DPSS' laser system
(click pictures to see a higher resolution image)

System Configurations After Install

The top reasons why you should NOT buy a DPSS laser system.

(e.g. DPSS Lasers Model(s) 3504 / 3501)

1. The IR laser diodes are in the laser head
   • Diodes are a consumable item; you can't replace the diodes without replacing the entire laser head. Down time is an issue, ~ 8 to 12 weeks.
   • Diodes are a source of heat; heat in the laser head will cause the system to detune over time creating a loss in power.
   • Upon diode failure, complete laser system must be returned to factory. Laser head & electronics are "matched." Down time is an issue. 
2. The doubling and tripling crystals are intra-cavity
   • The doubling and tripling crystals degrade with use. When the crystals degrade the entire laser head needs to be replaced, this part of the unit is not field serviceable. Again, down time is an issue.
   • The crystals are being exposed to a much higher average power; the crystals will have a much shorter lifetime.
   • Translating the crystals after degradation will cause the laser cavity to misalign. This is not a user friendly procedure. Re-alignment of SLA optics is a must.
3. The pulse width of the DPSS lasers are 25 nsec / 50 nsec respectively.
   • Longer pulse widths result in much lower pulse peak powers. In order to compensate for the lower peak power, much higher average power is incident on the doubling and tripling crystals. (Causing fast degradation of the crystals)
4. Solid state resin
   • The solid state resins were originally developed & characterized with a (10 nsec / 22khz / 400Mw) specific peak pulse power of 1820 Watts (the same laser as Laser Innovations')
   • The DPSS Laser Model 3501 (50nsec / 70khz / 500mW) has a peak pulse power of 143 Watts.
5. No IR modulator
   • An external UV modulator must be used, which is much lower in efficiency; resulting in much less average power (and much less peak pulse power).
   • The doubling and tripling crystals will be exposed to much higher IR power levels, which will result in much shorter lifetimes.
6. The laser system is water-cooled, and requires an external water to air heat exchanger.
7. Since all non-linear elements (doubler / tripler) are intra-cavity, any changes to the output power will result in major changes to the beam diameter, divergence, focal plane, astigmatism, mode quality, and most importantly "spot-size" at the Vat.
8. The DPSS laser uses the A/O modulator currently in the SLA-500 
   • This A/O modulator was designed to be used with a CW Argon ion laser, and will not perform correctly with a PULSED Solid state laser. Accuracy will be effected, de-lamination may occur, and "tagging" can be seen.
   • Resin will "age" faster, and become viscous - do to this excess UV light.
   • This optical element proves to be a 10% to 15% loss in power at the vat.
   • An external UV acoustic optical modulator must be used. 20:1 extinction ratio is typically what is found in the SLA-500. This is ~5 milliWatts of loss for every 100milliWatts. (Our internal IR AOM has an extinction ratio of 200:1, or greater.)
9. Laser system is controlled only through manual "ON/OFF" operation. This system is not integrated into the SLA-500 Build Station's software, nor was it specifically designed for this OEM application.
10. This laser system is water-cooled. The connectors used under the laser head can, and do cause possible leaks. We have several incidents recorded by SLA-250 & SLA-500 customers.
11. Reliability issues. 
    • Current customers have replaced lasers as often as 5x in a year, on one machine. This results in a large amount of "down-time", or extended periods of "Low power" conditions, which result in very lengthy build times.
    • Several customers have "exchanged" their DPSS laser, for a Spectra-Physics Laser. 
12. Why must the customer "prepay" the full laser price for year #2, if the laser is working? 
13. In most cases, the laser system cannot be repaired "on-site" - it must be shipped back to the factory, on a "swap-out" basis for diode replacement, and other optical or electrical components.
14. No remote control of power, or any other parameters from the laser. No external 
    display to verify the power, rep-rate, or any other diagnostic status of the laser.
    • These laser systems are not UL-listed, or CE certified - most commercial insurance policies require this for your protection. 
15. Laser life time (in hours) vs. SLA machine life time (in hours) 
    • This Laser will drop in power when the SLA-500 system goes through the normal "laser ON" and "laser OFF" build cycle of the machine. That is why the company recommends that you leave the laser system on all the time, (24/7) even when the machine is not in use. Always using up valuable laser lifetime, even when the machine is not building. 
      The software on the SLA-500 machine was originally designed to optimize laser life, for the Argon laser. When the build was complete, the software would turn the laser system "Off", saving hours of laser life until the next build was started. This would increase the laser lifetime, and as a bonus; show the depreciation of the laser cost (in hours) over the actual build time (in hours), to the accountants - as a direct comparison.

    DPSS - The company, & some history

16. Formerly part of Liconix Lasers. Melles Griot purchased Liconix lasers, but did not want and refused to pay for this DPSS technology. (Liconix also approached Laser Innovations, Laser Innovations also declined their offer of this technology, and their Ion laser technology as well.)
17. Total number of employees ~9, only 1 FE ( subcontracted ) for stereo lithography. 
18. Presently is 2 years old, and… 
    • Since Founded in 1998, the company's President ( & co-founder) has left that position. (2 presidents in two years.) 
    • Their Sales & Marketing manager (& co-founder, Mr. Ken Ibbs,) has left the company.
    • 2 of the 3 original co-founders have left the company.
19. Less than 3 years experience in field service, or OEM customer support, in this market.
20. 3D Systems currently buys the Spectra-Physics laser. (probably at a much higher price than they would pay for a DPSS Laser system). 3D Systems evaluated but, would not use their laser system. 
    #1 reason not to use; not FIELD SERVICEABLE.
21. Pricing for their upgrade package in mid to late 1999 was advertised for well over $100,000.00.
    Less than a year later (4 months), their advertised price was $60,000.00. An instant 40% depreciation incurred for several customers. (So much for the amortized value ?) Now it is currently selling for ~$20,000.00.
22. All key internal laser components are out-sourced. IR Diodes, ND:YV04 rods, doubler & tripler crystals, optics, and their mounting assemblies.
23. They do not provide a trade-in credit memo, nor will they purchase
    • your Coherent Argon Ion laser system. 
    • your Omnichrome, or Liconix HeCd laser system. 
24. The company is not ISO-9000 certified.
25. Bonus reason - Find a single customer who has one system with 5,000 hours of trouble free use. Spectra Physics has over 300 hundred of the UV systems, over a wide range of customers, who do have 5,000+ hours of trouble free use.