Features of LEXEL™ Lasers We're proud of the quality that goes into every LEXEL™ laser. Our engineers sweat over every detail of materials and design. The pages below explain the advanced features of our lasers, and how these features benefit you. Take a look and see why LEXEL™ is the most rugged, stable ion laser available. Laser head Plasma tube Optical resonator Power supply - Power supply interior Single-frequency operation - Model 503 Etalon - Typical frequency stability