bsrt optics design bi days 24 th november 2011 aurélie rabiller be-bi-pm
Post on 23-Dec-2015
215 Views
Preview:
TRANSCRIPT
BSRTOptics Design
BI Days24th November 2011
Aurélie RabillerBE-BI-PM
BI Days 2011 - BSRT Optics Design 2
Summary
• BSRT Overview Light sources, optics
• Present system: spherical mirrors Advantages Limitations and encountered problems
• New system under study: lenses Advantages Limitations Abort gap monitor line modification
BI Days 2011 - BSRT Optics Design 3
BSRT Layout
BSRT: Beam Synchrotron Radiation TelescopeBeam transverse profile monitoring with
synchrotron light
Optical line shared with: Abort gap monitor Longitudinal density monitor
Slow camera (BSRTS)
Fast camera (BSRTF)
Abort Gap Monitor (AGM)
Long. Density Monitor (LDM)
Optical delay line
Neutral filtersColor filters
Proton/Ion beam
90 %10 %
60 %40 %
10 %90 %
Motorized mirror
Extraction mirror
Two systems in LHC One system in lab
BI Days 2011 - BSRT Optics Design 4
Synchrotron light sources
Light sources:• Dipole (edge to center): Visible light from 1.3 to 7 TeV• Undulator especially design to create visible light from 450 GeV to 1.3 TeV
Undulator Dipole D3Extraction mirror in beam pipe
Syncro light from und.
Syncro light from dipoleProton/ion beam
0m 0.7m 1.6m 6.3m 27.6m
BI Days 2011 - BSRT Optics Design 5
Imaging system
• first focusing element: f= 4 - 5m inverted intermediate image with mag = 0.15 - 0.2
• second focusing element: f= 0.3 - 0.8m final image with mag = 0.3 - 0.6
28-32m 4-5m 0.5-1m 1-2m
ObjectIntermediate image
Final image
The system is limited by diffraction: the smaller the wavelength, the smaller the aberration => use of bandpass filters
BI Days 2011 - BSRT Optics Design 6
Some pictures
BI Days 2011 - BSRT Optics Design 7
Present design: spherical mirrors
1. Motorized 8 mirrors “trombone” to follow light source
2. Spherical mirror f=4000mm (F1)
3. Spherical mirror f=750mm (F2)
4. Cameras
• Total magnification: 0.3 (0.14 @ intermediate image plane)
F1
F2Entrance mirror
90%R Window
1
23
4
BI Days 2011 - BSRT Optics Design 8
Present design: Advantages
No chromatic aberrations
PSF ≈ 18um for all wavelength’s
Object Plane
Image Plane
350nm: PSF = 18um 450nm: PSF = 18um
550nm: PSF = 18um 600nm: PSF = 18um
1mm
Image of 1mm grid object
S u r f a c e I M A : C a m e r a
100.00
O B J : 0 . 0 0 0 0 , 0 . 0 0 0 0 m m
I M A : 0 . 0 0 0 , 0 . 0 0 0 m m
0 . 3 5 0 0
A u r e l i e - B S R T - B 1 - 2 0 - 1 0 - 2 0 1 1 . z m xC o n f i g u r a t i o n 1 o f 1
S p o t D i a g r a m
2 3 / 1 1 / 2 0 1 1 U n i t s a r e µ m .F i e l d : 1R M S r a d i u s : 1 0 . 4 7 1G E O r a d i u s : 1 7 . 6 8 2S c a l e b a r : 1 0 0 R e f e r e n c e : C h i e f R a y
S u r f a c e I M A : C a m e r a
100.00
O B J : 0 . 0 0 0 0 , 0 . 0 0 0 0 m m
I M A : 0 . 0 0 0 , 0 . 0 0 0 m m
0 . 4 5 0 0
A u r e l i e - B S R T - B 1 - 2 0 - 1 0 - 2 0 1 1 . z m xC o n f i g u r a t i o n 1 o f 1
S p o t D i a g r a m
2 3 / 1 1 / 2 0 1 1 U n i t s a r e µ m .F i e l d : 1R M S r a d i u s : 1 0 . 4 7 1G E O r a d i u s : 1 7 . 6 8 2S c a l e b a r : 1 0 0 R e f e r e n c e : C h i e f R a y
S u r f a c e I M A : C a m e r a
100.00
O B J : 0 . 0 0 0 0 , 0 . 0 0 0 0 m m
I M A : 0 . 0 0 0 , 0 . 0 0 0 m m
0 . 5 5 0 0
A u r e l i e - B S R T - B 1 - 2 0 - 1 0 - 2 0 1 1 . z m xC o n f i g u r a t i o n 1 o f 1
S p o t D i a g r a m
2 3 / 1 1 / 2 0 1 1 U n i t s a r e µ m .F i e l d : 1R M S r a d i u s : 1 0 . 4 7 1G E O r a d i u s : 1 7 . 6 8 2S c a l e b a r : 1 0 0 R e f e r e n c e : C h i e f R a y
S u r f a c e I M A : C a m e r a
100.00
O B J : 0 . 0 0 0 0 , 0 . 0 0 0 0 m m
I M A : 0 . 0 0 0 , 0 . 0 0 0 m m
0 . 6 0 0 0
A u r e l i e - B S R T - B 1 - 2 0 - 1 0 - 2 0 1 1 . z m xC o n f i g u r a t i o n 1 o f 1
S p o t D i a g r a m
2 3 / 1 1 / 2 0 1 1 U n i t s a r e µ m .F i e l d : 1R M S r a d i u s : 1 0 . 4 7 1G E O r a d i u s : 1 7 . 6 8 2S c a l e b a r : 1 0 0 R e f e r e n c e : C h i e f R a y
100
um
100
um
100
um
100
um
BI Days 2011 - BSRT Optics Design 9
Present design: Limitations
• Aperture: only 26% efficiency @ 450GeV for one pass
trombone, even less with two pass trombone
• Alignment of the trombone really difficult and needs frequent
retuning => efficiency is even more reduced
• Transmission: 8 mirrors trombone = 30% intensity loss (even more @ 400nm)
Less light collected => larger bandpass filter=> bigger aberration due to diffraction
BI Days 2011 - BSRT Optics Design 10
Present design: Limitations
• Design in reflection
small angles in X plane, back and forth optical path’s really close to
each other
Tight space for inserting elements without intercepting the light
• Abort Gap coupled to BSRT
steering done with the 1st mirror, in common with BSRT
BI Days 2011 - BSRT Optics Design 11
Present design: Limitations
Emittance measurement:
At present, PSF is more than 300um and not constant
Possible causes:
Diffraction
Vibrations
Alignment changes
Idea: Simplify the optical system :
More reliable alignment
Reduce vibration
BI Days 2011 - BSRT Optics Design 12
New design: Lenses
1. Lens optimized between 350 and 600nm, f=5000mm (L1)
2. 2 fold mirrors
3. Optimized lens f=300mm (L2) on motorized TS to follow light source
4. Camera
• Total magnification: 0.6 (0.21 @ intermediate image plane)
• Separate line for abort gap monitor by adding splitter before 1st mirror
1
2 3 4
BI Days 2011 - BSRT Optics Design 13
New design: Advantages
• No more trombone: only 2 mirrors in the system instead of 8
=> intensity loss ≈ 10%
• Aperture increased: 1st lens closer to entrance mirror
=> efficiency @ 450 GeV ≈ 42%
• Much easier alignment
• No more small angles in X plane due to reflection: more room
for inserting elements
• Abort gap monitor decoupled: in view of future interlock
system
BI Days 2011 - BSRT Optics Design 14
New design: Limitations
• Chromatic aberrations: lenses for 350 to 600nm region, but
not as good as spherical mirrors, PSF ≈30um
S u r f a c e I M A : I M G
100.00
O B J : 0 . 0 0 0 0 , 0 . 0 0 0 0 m m
I M A : 0 . 0 0 0 , 0 . 0 0 0 m m
0 . 3 5 0 0
B S R T _ M a g 0 6 _ 0 5 - 0 9 - 2 0 1 1 _ C o r r e c t e d _ D o u b l e t 2 _ a n d _ F 3 0 0 _ 2 . z m xC o n f i g u r a t i o n 1 o f 1
S p o t D i a g r a m
2 3 / 1 1 / 2 0 1 1 U n i t s a r e µ m .F i e l d : 1R M S r a d i u s : 1 0 . 0 9 2G E O r a d i u s : 2 4 . 5 9 3S c a l e b a r : 1 0 0 R e f e r e n c e : C h i e f R a y
S u r f a c e I M A : I M G
100.00
O B J : 0 . 0 0 0 0 , 0 . 0 0 0 0 m m
I M A : 0 . 0 0 0 , 0 . 0 0 0 m m
0 . 5 5 0 0
B S R T _ M a g 0 6 _ 0 5 - 0 9 - 2 0 1 1 _ C o r r e c t e d _ D o u b l e t 2 _ a n d _ F 3 0 0 _ 2 . z m xC o n f i g u r a t i o n 1 o f 1
S p o t D i a g r a m
2 3 / 1 1 / 2 0 1 1 U n i t s a r e µ m .F i e l d : 1R M S r a d i u s : 7 . 7 0 0G E O r a d i u s : 2 4 . 4 8 4S c a l e b a r : 1 0 0 R e f e r e n c e : C h i e f R a y
350nm: PSF = 25um 450nm: PSF = 13um
550nm: PSF = 25um 600nm: PSF = 57um Image of 1mm grid object
S u r f a c e I M A : I M G
100.00
O B J : 0 . 0 0 0 0 , 0 . 0 0 0 0 m m
I M A : 0 . 0 0 0 , 0 . 0 0 0 m m
0 . 4 5 0 0
B S R T _ M a g 0 6 _ 0 5 - 0 9 - 2 0 1 1 _ C o r r e c t e d _ D o u b l e t 2 _ a n d _ F 3 0 0 _ 2 . z m xC o n f i g u r a t i o n 1 o f 1
S p o t D i a g r a m
2 3 / 1 1 / 2 0 1 1 U n i t s a r e µ m .F i e l d : 1R M S r a d i u s : 1 0 . 1 0 2G E O r a d i u s : 1 2 . 9 2 7S c a l e b a r : 1 0 0 R e f e r e n c e : C h i e f R a y
S u r f a c e I M A : I M G
100.00
O B J : 0 . 0 0 0 0 , 0 . 0 0 0 0 m m
I M A : 0 . 0 0 0 , 0 . 0 0 0 m m
0 . 6 0 0 0
B S R T _ M a g 0 6 _ 0 5 - 0 9 - 2 0 1 1 _ C o r r e c t e d _ D o u b l e t 2 _ a n d _ F 3 0 0 _ 2 . z m xC o n f i g u r a t i o n 1 o f 1
S p o t D i a g r a m
2 3 / 1 1 / 2 0 1 1 U n i t s a r e µ m .F i e l d : 1R M S r a d i u s : 2 4 . 2 9 8G E O r a d i u s : 5 6 . 7 2 7S c a l e b a r : 1 0 0 R e f e r e n c e : C h i e f R a y
1mm
100
um
100
um
100
um
100
um
BI Days 2011 - BSRT Optics Design 15
New Design for Abort Gap
• Beam splitter T=92% above entrance mirror
• F=2000mm plano-convex lens
• 2 fold mirrors (one motorized)
• Camera to check beam presence and alignment
BI Days 2011 - BSRT Optics Design 16
Lab and tunnel test plan
BSRT:
Test in lab to validate the system as completely as possible
Magnification, aberrations, transmission, alignment procedure...
Abort Gap Monitor:
Test in lab (mostly alignment procedure)
Installation in the tunnel on one side during the shutdown
In addition to the present system
spare
BI Days 2011 - BSRT Optics Design 18
BSRT in LHC
D3 Dipole
Sync. Rad. Monitors
SC Undulator
top related