Er:YAG Laser Crystal
Erbium Substituted : Yttrium Aluminium Garnet
Lasers powered by Er:YAG (erbium substituted: yttrium aluminium garnet), operating at 2.94 microns, crystals couple well into water and body fluids. This is especially useful for applications in the fields of laser medicine and dentistry. The output of Er:YAG enables the painless monitoring of blood sugar levels, while safely reducing the risk for infection. It is also effective for laser treatment of soft tissue, such as cosmetic resurfacing. It is equally useful for treating hard tissue such as tooth enamel.
Er:YAG enjoys an advantage over other laser crystals in the 2.94 micron range in that it employs YAG as the host crystal. The physical, thermal and optical properties of YAG are widely known and well understood. Laser designers and operators can apply their depth of experience with Nd:YAG laser systems to achieve superior performance from 2.94 micron laser systems using Er:YAG.
Proprietary technology allows the production of Er:YAG crystals of excellent optical quality, low scattering losses; having higher efficiency, higher output and higher damage threshold. This technology allows the material to overcome the poor efficiency once associated with the use of 2.94 micron wavelength laser material.
Er:YAG laser crystals in sizes from 3 mm to 10 mm diameter, with lengths up to 150 mm long. Call upon our depth of experience in research, crystal growth and laser rod fabrication. Roditi will work with you to produce laser crystals that meet the exact specifications for superior performance of your 2.94 micron ER:YAG laser system.
Applications
- Designed for 2.94 µm output wavelength output wavelength Er:YAG is an excellent choice for Medical Laser Systems.
- Dental Laser Systems.
Optical and Laser Properties
| Laser Action | 4 Level Laser | Lower Level | 4I13/2 |
| Output Wavelength | 2.94 µm at 20°C | Upper Level Lifetime | 100 µsec |
| Emission Cross Section | Σ = 2.1 x 10-20 cm2 | Refractive Index | 1.838 at 632.8 nm |
| Upper Laser Level | 4I11/2 | Chemical Formula | Y(3 -x)Al5O12:Er(x) (50% Er) |
Absorption Bands
| 0.80µm (4I15/2 - 4I9/2) | 0.52µm (4I15/2 - 2H11/2) | 0.44µm (4I15/2 - 4F3/2) |
| 0.65µm (4I15/2 - 4F9/2) | 0.49µm (4I15/2 - 4F7/2) | 0.41µm (4I15/2 - 2H 9/2) |
| 0.54µm (4I15/2 - 4S3/2) | 0.45µm (4I15/2 - 4F5/2) | 0.38µm (4I15/2 - 4G11/2) |
Er:YAG Laser Rod Standard Fabrication Specifications
| Feature | Standard | Special Order |
| Crystal Orientation | <111> within 5° | Available |
| Diameter | 3 mm to 8mm | Available |
| Daimeter Tolerance | +0.0 mm/- 0.05 mm | Available |
| Length (plano/plano) | 30 mm to 150 mm | Available |
| Length Tolerance | ± 0.75 mm | ± 0.50 mm |
| Perpendiculairity of End Faces (plano/plano) | 5 arc-minutes | 2 arc-minutes |
| Parallelism of End Faces (plano/plano) | 10 arc-seconds | |
| Flatness | 0.1 wave maximum | 0.10 wave maximum |
| (plano/plano) | over 90% of aperture | over full aperture |
| Surface Finish at 5X | 20-10 (scratch & dig) | 10-5 (scratch & dig) |
| Barrel Finish | 400 grit | Polished approx. 80-50 |
| End Face Bevel | 0.075 mm to 0.12 mm at 45° angle | |
| Chips | No chips allowed on end face of rod; chip having maximum length of 0.3 mm permitted to lie in the area of bevel and barrel surfaces. | |
| End Configurations | plano/plano, plano/wedge, wedge/wedge or Brewster cut. Plano ends can be finished flat, concave or convex | |
| Coatings | Standard coating is AR at 2.94 µm with R<0.25% each face. Other coatings available. | |