def CDAbeam(num, div, pitch, roll, cda):
## PT.transform(*cda)
PT.pointsource(div, num)
PT.transform(0, 0, 0, pitch, 0, 0)
PT.transform(0, 0, 0, 0, 0, roll)
PT.itransform(*cda)
return
def traceBeam(gratAlign,order=1.,wave=2.48,blaze=30.):
"""Traces a beam to grating, applies misalignment,
then traces to focal plane and returns mean
x,y position
x refers to spectral direction
"""
#Compute yaw to achieve Littrow configuration
phi0 = arccos(sin(1.5*pi/180)/cos(blaze*pi/180))
yaw = -tan(sin(blaze*pi/180)/tan(phi0))
## yaw = yaw - pi/2
## pdb.set_trace()
#Set up beam
rays = PT.pointsource(0.,10) #multiple rays to avoid Python complaints
#Rotate to nominal grating reference frame
PT.transform(rays,0,0,0,pi/2+1.5*pi/180,0,0)
#Apply misalignment
PT.transform(rays,*gratAlign)
#Trace grating
PT.flat(rays)
PT.transform(rays,0,0,0,0,0,yaw) #-1.73211678*pi/180
PT.radgrat(rays,11500.,160./11500.,order,wave)
PT.itransform(rays,0,0,0,0,0,yaw)
#Reverse misalignment
PT.itransform(rays,*gratAlign)
#Trace to focal plane
PT.transform(rays,0,11500.,0,0,0,0)
PT.transform(rays,0,0,0,pi/2,0,0)
PT.flat(rays)
#Return mean positions
return mean(rays[1]),mean(rays[2])
def sphericalNodes(rin,z0,fov,Nshells,N):
"""This function will iteratively scan node positions
about a sphere around the focus. Node will start in obvious
vignetting position. Extreme rays will be traced including
FoV. Node will be nudged outward until vignetting no longer
occurs. Node will then be moved by the designated mechanical
gap. Then the next node is traced in the same fashion.
Assumptions: 50 mm symmetric gap
"""
#Bookkeeping parameters
f = np.sqrt(rin**2+z0**2)
fov = fov/60.*np.pi/180. #fov to radians
zlist = []
rlist = []
for i in range(Nshells):
#Starting radius for next shell node
rstart = PT.wsPrimRad(z0+225.,1.,rin,z0)
#Reduce rstart until vignetting is reached
flag = 0
while flag==0:
zstart = np.sqrt(f**2-rstart**2)
#Set up rays
r1 = PT.wsPrimRad(zstart+25.,1.,rstart,zstart)
r2 = PT.wsPrimRad(zstart+225.,1.,rstart,zstart)
PT.pointsource(0.,N)
PT.z = np.repeat(10500.,N)
PT.x = np.linspace(r1,r2,N)
PT.n = np.repeat(-1.,N)
#Perform trace and add FoV deflections to rays
PT.wsPrimary(rstart,zstart,1.)
PT.l = np.repeat(np.sin(fov),N)
PT.n = -np.sqrt(1 - PT.l**2)
#Verify that rays do not hit prior primary
PT.wsPrimary(rin,z0,1.)
if np.sum(PT.z<z0+225.) != 0:
#Ray has hit
print 'Ray hits prior primary!'
flag = 1
#Verify that rays do not hit prior secondary
PT.wsPrimary(rstart,zstart,1.)
PT.reflect()
PT.wsSecondary(rstart,zstart,1.)
PT.reflect()
PT.wsSecondary(rin,z0,1.)
if np.sum(PT.z > z0-225.) != 0:
print 'Ray hits prior secondary!'
flag = 1
#Look at other deflection
PT.pointsource(0.,N)
PT.z = np.repeat(10500.,N)
PT.x = np.linspace(r1,r2,N)
PT.n = np.repeat(-1.,N)
#Perform trace and add FoV deflections to rays
PT.wsPrimary(rstart,zstart,1.)
PT.l = np.repeat(-np.sin(fov),N)
PT.n = -np.sqrt(1 - PT.l**2)
#Verify that rays do not hit prior primary
PT.wsPrimary(rin,z0,1.)
if np.sum(PT.z<z0+225.) != 0:
#Ray has hit
print 'Ray hits prior primary!'
flag = 1
#Verify that rays do not hit prior secondary
PT.wsPrimary(rstart,zstart,1.)
PT.reflect()
PT.wsSecondary(rstart,zstart,1.)
PT.reflect()
PT.wsSecondary(rin,z0,1.)
if np.sum(PT.z > z0-225.) != 0:
print 'Ray hits prior secondary!'
flag = 1
if flag==0:
rstart = rstart - .01 #Take off 10 microns
## sys.stdout.write(str(rstart)+'\n')
## sys.stdout.flush()
#Vignetting has been reached, append rstart and zstart
#to list of node positions
rlist.append(rstart)
zlist.append(zstart)
rin = rstart
z0 = zstart
return rlist,zlist