How to use the raytracing.Lens function in raytracing

from raytracing import ImagingPath, Space, Lens, Aperture

'''Demo #4 - Aperture behind lens
Notice the aperture stop (AS) identified after the lens, not at the lens. Again, since there is no field stop,
we cannot restrict the object to the field of view because it is infinite.'''


path = ImagingPath()
path.label = "Demo #4: Aperture behind lens"
path.append(Space(d=10))
path.append(Lens(f=5, diameter=3))
path.append(Space(d=3))
path.append(Aperture(diameter=3))
path.append(Space(d=17))
path.display()

from raytracing import ImagingPath, Space, Lens


'''Demo #13: - An object at z=0 (front edge) is used. It is shown in blue. The image (or any intermediate images) are shown in red.\n\
This will use the default objectHeight and fanAngle but they can be changed with:
path.objectHeight = 1.0
path.fanAngle = 0.5
path.fanNumber = 5
path.rayNumber = 3'''


M1 = Space(d=10)
M2 = Lens(f=5)
M3 = M2 * M1
print(M3.forwardConjugate())
print(M3.backwardConjugate())

from raytracing import ImagingPath, Space, Lens, Aperture

'''
    Demo #10 - A retrofocus has a back focal length longer than the effective focal length. It comes from a diverging lens followed by a converging
    lens. We can always obtain the effective focal lengths and the back focal length of a system.
'''


path = ImagingPath()
path.fanAngle = 0.05
path.append(Space(d=20))
path.append(Lens(f=-10, label='Div'))
path.append(Space(d=7))
path.append(Lens(f=10, label='Foc'))
path.append(Space(d=40))
(focal, focal) = path.effectiveFocalLengths()
bfl = path.backFocalLength()
path.label = "Demo #10: Retrofocus $f_e$={0:.1f} cm, and BFL={1:.1f}".format(focal, bfl)
path.display()

from raytracing import ImagingPath, Space, Lens

'''Demo #3 - A finite lens
   An object at z=0 (front edge) is used with default properties (see Demo #1). Notice the aperture stop (AS)
   identified at the lens which blocks the cone of light. There is no field stop to restrict the field of view,
   which is why we must use the default object and cannot restrict the field of view. Notice how the default
   rays are blocked.'''


path = ImagingPath()
path.label = "Demo #3: Finite lens"
path.append(Space(d=10))
path.append(Lens(f=5, diameter=2.5))
path.append(Space(d=3))
path.append(Space(d=17))
path.display()

'''Demo #5 - Simple microscope system
The aperture stop (AS) is at the entrance of the objective lens, and the tube lens, in this particular microscope, is
the field stop (FS) and limits the field of view. Because the field stop exists, we can use limitObjectToFieldOfView=True
when displaying, which will set the objectHeight to the field of view, but will still trace all the rays using our parameters.
'''

path = ImagingPath()
path.label = "Demo #5: Simple microscope system"
path.fanAngle = 0.1  # full fan angle for rays
path.fanNumber = 5  # number of rays in fan
path.rayNumber = 5  # number of points on object
path.append(Space(d=4))
path.append(Lens(f=4, diameter=0.8, label='Obj'))
path.append(Space(d=4 + 18))
path.append(Lens(f=18, diameter=5.0, label='Tube Lens'))
path.append(Space(d=18))
path.display()

from raytracing import ImagingPath, Space, Lens

'''Demo #2 - Two lenses, infinite diameters
An object at z=0 (front edge) is used with default properties (see Demo #1).'''


path = ImagingPath()
path.label = "Demo #2: Two lenses, infinite diameters"
path.append(Space(d=10))
path.append(Lens(f=5))
path.append(Space(d=20))
path.append(Lens(f=5))
path.append(Space(d=10))
path.display()

'''
    Demo #6 - Simple microscope system, only principal rays
    The aperture stop (AS) is at the entrance of the objective lens, and the tube lens, in this particular microscope, is
    the field stop (FS) and limits the field of view. Because the field stop exists, we can use limitObjectToFieldOfView=True
    when displaying, which will set the objectHeight to the field of view. We can also require that only the principal rays are drawn: chief ray
    marginal ray (or axial ray).
'''


path = ImagingPath()
path.label = "Demo #6: Simple microscope system, only principal rays"
path.append(Space(d=4))
path.append(Lens(f=4, diameter=0.8, label='Obj'))
path.append(Space(d=4 + 18))
path.append(Lens(f=18, diameter=5.0, label='Tube Lens'))
path.append(Space(d=18))
path.display()

from raytracing import ImagingPath, Space, Lens

'''Demo #1 - An object at z=0 (front edge) is used. It is shown in blue. The image (or any intermediate images) are shown in red.\n\
This will use the default objectHeight and fanAngle but they can be changed with:
path.objectHeight = 1.0
path.fanAngle = 0.5
path.fanNumber = 5
path.rayNumber = 3'''


path = ImagingPath()
path.label = "Demo #1: lens f = 5cm, infinite diameter"
path.append(Space(d=10))
path.append(Lens(f=5))
path.append(Space(d=10))
path.display()

from raytracing import ImagingPath, Space, Lens, Aperture, DielectricSlab

'''
    Demo #7 - Focussing through a dielectric slab
'''


path = ImagingPath()
path.label = "Demo #7: Focussing through a dielectric slab"
path.append(Space(d=10))
path.append(Lens(f=5))
path.append(Space(d=3))
path.append(DielectricSlab(n=1.5, thickness=4))
path.append(Space(d=10))
path.display()

from raytracing import ImagingPath, Space, Lens, Aperture


'''
    Demo #8 - Virtual image at -2f with object at f/2
'''


path = ImagingPath()
path.label = "Demo #8: Virtual image at -2f with object at f/2"
path.append(Space(d=2.5))
path.append(Lens(f=5))
path.append(Space(d=10))
path.display()