1
ZTF Detector/Filter Combinations
P. Jelinsky
2013-02-19
2
Optics Outline
• Look at different number of detectors
– Can the sky be tiled?
• Do not consider gaps.
• Do not consider mapping unto a sphere
– Can it use fixed filters efficiently
– Does it have a viable stagable option?
3
7 detectors
• Cannot use fixed filters efficiently
(since odd number of detectors)
• Can tile the sky efficiently
• No feasible stagable options.
• Maximum off axis angle: 3.2°
Tile Example
No Vignetting
10%Vignetting
20%Vignetting
30%Vignetting
4
8 detectors
• Can use fixed filters efficiently
• Can tile the sky efficiently
• Has a feasible stagable option.
– Start with 4 detectors along center line
• Maximum off axis angle: 3.6°
Fixed Filter Layout
4 Filter Stage
No Vignetting
10%Vignetting
20%Vignetting
30%Vignetting
5
8 detectors (cont)
Tile Example
Fixed Filter Tile Example
(Shift 2 detectors horizontal)
(then shift 2 detectors vertical)
6
9 detectors
• Cannot use fixed filters efficiently
• Can tile the sky efficiently
• No feasible stagable option.
• Maximum off axis angle: 3.8°
Tile Example
No Vignetting
10%Vignetting
20%Vignetting
30%Vignetting
7
10 detectors
• Can use fixed filters efficiently
• Can tile the sky efficiently
• Has feasible stagable option.
– 6 detectors
• Maximum off axis angle: 3.8°
Fixed Filter Layout
6 Detector Stage
No Vignetting
10%Vignetting
20%Vignetting
30%Vignetting
8
10 detectors (cont)
Tile Example
Filter Tile Example
(Do tile pattern to left)
(then shift 1 detectors horizontal)
9
12 detectors
• Can use fixed filters efficiently
• Can tile the sky efficiently
• Has feasible stagable option.
– 8 detectors
• Maximum off axis angle: 4.1°
Fixed Filter Layout
8 Detector Stage
No Vignetting
10%Vignetting
20%Vignetting
30%Vignetting
10
12 detectors (cont)
Tile Example
Filter Tile Example
(Shift 2 detectors horizontal)
(then shift 3 detectors vertical)
11
Conclusion
• 12 detector option is the most flexible
– Can come on line early with 8 detectors (if needed)
– Can use fixed filters (if acceptable)
– Can tile the sky efficiently
• The major issue is cost