800nm Chirped Mirror HD116-25.4-6.35

Overview

The 800nm Chirped Mirror -250fs² (HD116-25.4-6.35) from Ultrafast Innovations delivers precision negative group delay dispersion (GDD) of -250 fs² per bounce across 700–870 nm, centered at 785 nm. Engineered for Ti:Sapphire oscillators, CPA systems, and OPCPA setups, this S-polarized chirped mirror at 7° AOI provides mid-range GDD compensation ideal for external compressors and pulse stretching applications requiring 24 bounces to offset approximately 6000 fs² of accumulated positive dispersion.

This 785nm chirped mirror occupies a critical niche between low-dispersion intracavity mirrors and ultra-high-GDD bulk compressors. The -250 fs² specification enables compact compressor designs while maintaining manageable bounce counts, making it particularly suited for tabletop ultrafast systems where space constraints and alignment complexity must be balanced against dispersion management requirements. The broad 170 nm operational bandwidth supports sub-20 fs pulse compression in Ti:Sapphire systems and wavelength-tunable OPA configurations.

Applications

• Ti:Sapphire CPA External Compressors: Pre-compensation of stretcher-induced positive GDD in regenerative and multipass amplifiers operating 750–850 nm
• OPCPA Pump Pulse Conditioning: GDD compensation for 800 nm pump beams in optical parametric chirped-pulse amplification chains
• Oscillator Dispersion Management: Fine-tuning intracavity GVD in extended-cavity Ti:Sapphire oscillators for optimized mode-locking bandwidth
• OPA Signal/Idler Compression: Pulse compression for 700–870 nm tunable outputs from Ti:Sapphire-pumped optical parametric amplifiers

Construction & Performance

Manufactured on 25.4 mm diameter × 6.35 mm thick UVFS substrates, the HD116 features ion beam sputtered (IBS) multilayer dielectric coatings optimized for S-polarization at 7° angle of incidence. The coating maintains R > 99% reflectance throughout the 700–870 nm range, ensuring minimal losses in multi-bounce compressor configurations. The precision-polished substrate and phase-matched layer structure deliver the specified -250 fs² GDD with minimal higher-order dispersion artifacts, critical for maintaining pulse fidelity in sub-50 fs regimes. LIDT rated at 0.2 J/cm² for femtosecond pulses.

Storage & Handling

Operate at 25 °C, 40–60% RH. Clean only with >99% optical-grade ethanol and lint-free lens tissue using single-pass drag method. Avoid abrasive cloths and water.