1. NGAO 1-tier Draft Optical Relay Design P. Wizinowich 12/7/07

2. D-IFS / LOWFS Focal Plane (150” dia field of view) Very similar to existing Keck AO optical relay: - Image rotator larger - Same OAPs (but larger diameter) - Same pupil size on DM - Same opening angle to DM - D-IFS & LOWFS at NIRC2 location D-IFS / LOWFS DM (woofer) OAP1 at 12.8 km conjugate OAP2

3. 150” Field to 2 nd Relay (150” dia field of view)

4. NGS WFS Focal Plane (30” dia field of view) 1. Mirror for NGS AO narrow field science 2. Open for d-IFS LGS AO science 3. JH transmissive, K-band reflective 4. JH transmissive, visible reflective 5. J transmissive, H-band reflective 6. H transmissive, < H-band reflective OAP3 OAP4 DM (tweeter) NGS WFS FSMs 2.3 m 2.2 m

5. NIR Camera Focal Plane (30” dia field of view) NIR Camera 1. Mirror for LGS science For NGS science: 2. JHK reflective, visible transmissive 3. IJHK reflective, visible transmissive 4. Open

6. Visible Camera Focal Plane (30” dia field of view) Visible Camera 1. Open for NIR science 2. Mirror for Vis science 3. I reflective, JHK transmissive dichroic for simultaneous Vis/NIR (option)

7. OSIRIS Focal Plane (30” dia field of view) OSIRIS (or DSM) 1. Open 2. K reflective, < K transmissive 3. H reflective, < H transmissive 4. J reflective, J transmissive OSIRIS position and optical relay same as for existing AO system.

8. Collimated Beam to Interferometer Dual Star Module ( 30” dia field of view) DSM 1. Open 2. JHK reflective, < J transmissive DSM position and optical relay same as for existing AO system.

9. LGS WFS & LGS ACAM Focal plane for 90 km LGS Folds beam vertically 1. Na Reflective Dichroic transmits > 650 nm 2. Open for NGS science (option) OAP2b (optimized for LGS) LGS WFS Focal Plane (150” dia field of view, LGS at 90 km) Fold Mirror Folds beam horizontal 400 mm above 1 st Relay

10. NGS Acquisition Camera Fold (150” dia field of view) Option 1. Horizontal (or vertical) Fold Option 2. Vertical Fold

11. Alignment, Calibration & Diagnostics (150” dia field of view) Pop-up mirror to DM interferometer Telescope Simulator Fold (option 1 is vertical) TS Option 2 TS Option 3