Rosco Laboratories 3660
1.5" x 2.5" Double Coated UV Pass Dichroic Filter

Dichroic filters are durable glass color filters that transmit only certain wavelengths of light, reflecting the rest of the spectrum, rather than absorbing it.  Since virtually no energy is absorbed by the filter, light transmission is significantly higher than traditional gels and will never burn out or fade.  Rosco Permacolor filters are made with the highest quality coatings, designed not to fade or shift color.  In addition, Rosco's sophisticated manufacturing process allows for precise color consistency batch to batch to a degree that is unprecedented in other dichroic coatings.  Permacolor filters are manufactured on durable borafloat glass 1.75mm (.069") thick.

Durable enough to withstand the extreme temperatures found in even the hottest luminaires, the Permacolor palette of standard colors offers designers a long life filter alternative to many of the most popular Rosco gel colors.

Rosco Permacolor dichroic filters are manufactured to exacting tolerances in a state-of-the-art, 36" vacuum deposition chamber.  This optimally sized manufacturing line allows for unprecedented control of color and film density.  Permacolor filters are extremely durable and precisely repeatable, meeting the high expectations of entertainment and architectural lighting designers throughout the world.

Description of Film: All films are manufactured using dielectric materials (TiO2 and SiO2) that are evaporated by an electron beam source in a high vacuum (10x-6 torr) and high temperature (>240ºC) environment.  This produces a dense film (85-90% packing density) that is highly resistant to damage from abrasion, humidity, chemicals and spectral radiation.  Under normal conditions, the life expectancy of these films is greater than 10 years.  However, dielectric films are porous by nature.  Long term exposure to high humidity or high temperature environments, may cause color shifts of ±5 nm.

• Cutting Tolerance:  ± .5mm
• Standard Thickness: 1.75mm ±.2mm
• Optional Thickness: 1.1mm ±.2mm
• Aperture: > 95% (guaranteed useable area)
• Surface Defects: 80 - 50- Mil. O-13830 Scratch/Dig Test (.08mm Scratch or .5mm Dig per 20 sq. Viewed by unaided eye w/40 watt source)
• Adhesion: Passes Mil. C-48497 (Cellophane Tape Test)
• Abrasion: Passes Mil. C-48497 (Moderate; 50 strokes with cheesecloth under 1 lb. force, and Severe, 20 strokes with coarse eraser under 2 lbs. of force)
• Temperature:
  Maximum Short Term (< 1 hour): -50º C to 450º C
  Maximum Continuous (> 24 hours): 200º C
  RTD < 90K (hot spotting)
• Humidity: Passes Mil. C-48497 (95 - 100% at 50º C per 24 hour period)
• Color Tolerance: ± 5nm of designed Half Height
• Angle of Incidence: 0º to 45º. Minimal shift (± 5nm) towards shorter wavelengths beyond this range.