2. Heritage from the LOFT-M3 study: Collimator Assembly
The LAD Assembly
Heritage from the LOFT-M3 study: Collimator Assembly

3. Microchannel Plate technology
The LAD Collimator
Microchannel Plate technology

4. The LAD Collimator plates requirements
Glass Type
High Lead content
Lead-oxide equivalent content
37% minimum
Aspect Ratio
60:1
Pore shape
squared
Pore size
83 m
Wall thickness
16 m (X-ray transparency 30 keV)
Open Area Ratio
70%
Plate thickness
6 mm
Plate size
mm x mm
Pore-to-pore alignment
1 arc minute
Pore to surface alignment
Plate flatness
Pore surface roughness
(nearly-)no reflection of X-rays down to 1 keV or
>13 nm rms micro-roughness
Surface coating
80 nm Aluminum self-standing coating on one side (TBC)
Natural radioactivity
7100 Bq/m2 (natural 40K)

5. The LAD Collimator plates
LOFT Baselines: - LOFT-M3: - Square pores - Photonis (France) manufacturer - ESA procurement - ESA TDA - Recommendation for a round pore approach - LOFT-M4: - Round pores - Hamamatsu (Japan) manufacturer - In-kind contribution by Japan

6. The LAD Collimator plates: Photonis option
Photonis: - Long heritage for manufacturing (MCPs for night vision) - ESA-supported Technology Development Activity in Full-scale, «almost» full-spec prototype developed and tested (still some reflection at low energies) – square pore - Expectation to reach 75% OAR (currently 70% demonstrated) - Credible (ESA-approved) production plan in place - Space heritage from BepiColombo on the way - High costs - Manufacturer in France, but no perspective CNES support - Need for ESA support

7. The LAD Collimator plates: Photonis option

8. The LAD Collimator plates: Photonis option

9. The LAD Collimator plates: Hamamatsu option
Hamamatsu: - Long heritage for manufacturing (MCPs) - ISAS-supported development activity - Small/Half-scale prototypes developed and tested - Development still required for: full-size, verify reduced reflection (>30nm declared), verify surface-pore alignment - High OAR (75%) and Pb content (>40%) - Credible production plan in place - Space heritage from MCPs - Low costs - Potential in-kind contribution from Japan

10. The LAD Collimator plates: Hamamatsu option
25 mm

11. The LAD Collimator plates: Hamamatsu option

12. The LAD Collimator plates
Conclusions: - The Photonis collimator is certainly the most mature technology for the eXTP application - However, the technology development required for the Hamamatsu supplier are considered not critical - The programmatic scenario appears more viable with Hamamatsu, which is now considered as the current baseline for the eXTP/LAD.