Image Intensifiers in Astronomy
-
Upload
quemby-kent -
Category
Documents
-
view
53 -
download
2
description
Transcript of Image Intensifiers in Astronomy
www.multimediatech.cz © Multimedia Technology Group
České vysoké učení technické v PrazeFakulta elektrotechnickáKatedra radioelektroniky
Technická 2166 27 Praha 6
29/4/2011
v1.00
IBW
S 2
011
, K
arlo
vy V
ary
MAIAMeteor Automatic Imager and Analyzer
Image Intensifiers
in
AstronomyStanislav Vítek, Karel Fliegel, Petr Páta, Pavel Koten
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
Outline of the talk
Motivation of our work
Description of MAIA system
Image intensifier: good for any science?
Movie
Experiences, conclusions
2/11
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
Motivation of our work
Observations of faint meteor showers
Requirements for equipment
Fast enough
High gain
Affordable
Requirements for technical properties are critical
Budget → limited
Human resources → better (students)
3/11
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
History
4/11
S-VHS camcorder
25 fps
Records on tapes
Jitter
No cover
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
Description of camera
Mechanical componets (A) Outer cover
• Videotec HEG47K2A000• Heating with thermostat• Internal dimensions 134x88x450mm
(B) Inner cover• Model Brůna I• Parts milled from solid aluminium• Precise adjust of all components
5/11
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
Description of camera
(2) Key electro-optical components (A) Outer lens
• Pentax SMC FA 1.4/50mm (K-Mount bayonet) (B) Image intensifier
• Philips (Photonis) XX1332• Aperture 50/40mm• Gain up to 60000 lm/lm• Resolution 30lp/mm
(C) Inner lens• Pentax H1214-M 1.4/12mm• Extension 250μm• C-Mount
(D) Camera• JAI CM-040GE• GigE Vision interface (8/10bpp), 1/2” progressive mono CCD• Resolution 776 x 582pix (0,45Mpix) ~PAL• Framerate 61,15fps
Black anodized inner cover
6/11
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
Overall description
2 stations (Kunžak a Odřejov) ~ 210Mbps (8bpp @ 60fps, custom video format) ~ 1TB / night video sequences ~ 10 min central DB, batch data processing
7/11
Camera Camera
PC Main PC
HDD array
GigE Vision
Internet
GigE Vision
92.5km
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
Image intensifier
Philips (Photonis) XX1332 Image intensifier for night vision Microchannel plate
8/11
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
Electro-optical properties
Spectral sensitivity ~ 455-845nm
Non-linear! Automatic gain control
400 500 600 700 800 9000
0.2
0.4
0.6
0.8
1
Wavelength [nm]
Re
lativ
e s
en
sitiv
ity,
Sp
ect
ral t
ran
smis
sio
n [
-]
LensB=0.11
B=0.23
B=0.36
B=0.47B=0.59 B=0.71
10-4
10-3
10-2
10-1
10010
-2
10-1
100
Normalized input power [-]
No
rma
lize
d g
ain
[-]
Overall spectral sensitivity AGC
9/11
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
Electro-optical properties
Spectral response of camera ~ 400-725nm
Spectrum on the output aperture of image intensifier ~ 487-571nm
Spectral sensitivity of camera Spectrum on the output of II
400 500 600 700 800 900 10000
0.2
0.4
0.6
0.8
1
Wavelength [nm]
Re
lativ
e r
esp
on
se,
Sp
ect
ral t
ran
smis
sio
n [
-]
Lens
Camera w/o lens
Camera with lens
400 500 600 700 800 900 10000
0.2
0.4
0.6
0.8
1
Wavelength [nm]
Re
lativ
e r
esp
on
se,
Re
lativ
e p
ow
er
[-]
Camera with lens
Relative power
10/11
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
Electro-optical properties
Overall resolution Limited by used camera (0,24Mpix in circular aperture)
Output aperture of image intensifier
0 200 400 600 800 1000 12000
0.2
0.4
0.6
0.8
1
Spatial frequency [LW/PH]
MT
F [
-]Overall MTF
Input lens andimage intensifier
JAI CM-040GE
Nikon D700
11/11
© Multimedia Technology Group
IBW
S 2
011
, K
arlo
vy V
ary
Experiences, Conclusions
Unprotected input aperture → Automatic iris should be designed
New system much better characteristics Not working continuously
12/11
www.multimediatech.cz © Multimedia Technology Group
České vysoké učení technické v PrazeFakulta elektrotechnickáKatedra radioelektroniky
Technická 2166 27 Praha 6
29/4/2011
v1.00
IBW
S 2
011
, K
arlo
vy V
ary
MAIAMeteor Automatic Imager and Analyzer
Thank for your attention