1. General Information

• Model: 7701A/E（3 mm beam, short‑range）

• Part Number: 7701‑6191‑0460；6191‑0460‑01 / ‑02

• Manufacturer: ZYGO（AMETEK）

• Type: Helium‑Neon (HeNe), CW, two‑frequency, linearly polarized laser head

• Application: High‑resolution laser interferometry（with ZMI‑2001/2002/4104）, semiconductor, ultra‑precision positioning, metrology, machine tools

• Dimensions: 450 × 100 × 80 mm（approx）

• Weight: 5.5 kg（12 lb）

2. Optical Specifications

• Wavelength: 632.8 nm（vacuum）

• Output Power:

  • Min: > 400 µW（0.4 mW）

  • Typ: 550–1000 µW（0.55–1 mW）

  • Max: < 1 mW

• Beam Diameter: 3 mm（for 2 m max range）

• Polarization: Two orthogonal linear polarizations

• Beat Frequency: 20 MHz ± 1600 Hz

• Wavelength Stability:

  • 24 h: ±0.01 ppm

  • Lifetime: ±0.1 ppm

• Beam Pointing Stability: < 0.1 arcsec/°C

• Max Measurement Range: 2 m（3 mm beam）

3. Electrical

• Power: ±15 VDC ±0.5 V

  • +15 V: 2.5 A

  • −15 V: 1.2 A

• Power Dissipation:

  • Warm‑up: 37 W

  • Operation: 27 W

• Warm‑up Time:

  • Light out: < 10 s（max 70 s）

  • Full spec: < 30 min（typically < 7 min）

4. Environmental

• Operating Temp: 10 °C to 30 °C

• Storage Temp: −40 °C to 75 °C

• Humidity: 0%–90% RH, non‑condensing

• Shock（Non‑op）: 40 G, 11 ms, 3 orthogonal axes

5. Key Features

• 3 mm beam for short‑range（2 m）applications

• Two‑frequency HeNe for sub‑nanometer interferometry

• Ultra‑stable wavelength（0.01 ppm/24 h）

• Low beam drift and high pointing stability

• Fully compatible with ZYGO ZMI‑2001/2002/4104 boards

6. Part Number Variants

• 6191‑0460‑01: Standard 7701A/E（3 mm beam）

• 6191‑0460‑02: Same as ‑01, different configuration（e.g., mounting）