Lessons Learned from FQPM & AIC

P. Baudoz, A. Boccaletti, D. Rouan, D. Mawet & Coronagraphy team @

Observatoire de Paris-Meudon

Achromatic Interfero Coronagraph

- 1996 : 10 years

OCA-STScI-ONERA 1997OCA-STScI-ONERA 1997

Separation = 1/3 of /D, K = 3.5

D=34r0(vis)

OCA-STScI-ONERA 1997

Gay & Rabbia 1996,CRAS ; Baudoz et al., 2000a, A&A ; Baudoz et al., 2000b, A&A

CIA @ CFHT

Baudoz et al., 2000, CFHT Bulletin

Adapting coronagraph to a existing design

here CFHT telescope: highly not optimized (secondary mirror > 30%)

Four Quadrant Phase Mask

manufactured and characterized for :- Visible (laboratory R&D) - Near IR (implemented on NACO/VLT)- For mid IR (JWST/MIRI project)- Near IR achromatic version (VLT/SPHERE

project)

+ pupil

Rouan et al., 2000, PASP ; Riaud et al., 2001, PASP ; Riaud et al. 2003, PASP

FQPM Visible Lab tests

10-6 @ 3/D

Riaud et al. 2003, PASP

Limited by an ocean of speckle at the 10-6 level

FQPM @ VLT

Boccaletti et al. ,2004, PASP ; Boccaletti et al. ,2007, in preparation

HIP 1306

= 0.128’’ – 1.075’’

m = 1 .6 – 3.5mag

seeing = 0.9’’

raw image

centrosymmetrical subtraction

• Contrast of 10-4 @ 0.5 ’’• A new device coupled with differential imaging will be implemented

FQPM @ VLT

Boccaletti et al. ,2007, in preparation

Information up to 13 AU (instead of 23 AU with Lyot coronagraph)

Active Galactic Nuclei : NGC1068

(Gratadour et al. 2003)

New structures revealed at both large and close separations (contrast of known strcutures is improved with respect to previous non-coronagraphic observations)

M fov=3.5‘’

Ks+4QPM, fov= 11.7‘’ Ks+4QPM, fov=3.5‘’

Large scale arclects structures (d=160pc)

micro spieal arms

(d=15pc)

south tail

aligned knots

NACO + 4QPM in Ks

Phase mask manufacturing (JWST-MIRI)

• possible manufacturing process :

ZnSe deposition (lift off)

Ge attack (reactive ion etching)

ZnSe attack (reactive ion etching)

Diamond attack (reactive ion etching)

0 200 400 600 800 µm

µm

0

100

200

300

400

500

600

700

800

nm

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

5500

6000

6500

7000

ZnSe deposition15m 4QPM

Diamond RIE 5m 4QPM

1 m

/D = 300m

GE RIE15m 4QPM

Baudoz et al., 2005b, PASP

10-5

FQPM Mid-Infrared Test @ 5m for MIRI/JWST

Precise information on optical materials unknown at very low temperature for these bandwidths

FQPM Achromatization - Halfwave plate

Development in the context of SPHERE (VLT Planet finder)

Mawet et al, 2006

FQPM - Visible Halfwave plate lab tests

• Contrast 10-5 @ 4 /D for large bandwidth• Expected contrast 10 to 100 times better with optimized half wave plate and R=5 to 20

MgF2

50 µm Prototypte IR Halfwave FQPM for SPHERE/VLT

Technique limited to 10-6 to 10-7 for large bandwidth

Mawet et al, 2006

• AR Coatings• image ghosts• pupil ghosts

• Optical quality of substrate • Fabrication specs

• transition• thickness of quadrant (chromaticity)• reproductibility of the specs

• Low temperature behaviour (optical index)• Telescope Specs (JWST, ground, etc…)• Moving specs (not in the right direction in general…)

Up to now : Adapt coronagraph to telescope

TPF-C : MUST NOT DO the opposite but

Design telescope and coronagraph together

Lessons Learned with AIC & FQPM Development