How can I rescale or zoom plot?

[khoroshyy]

Hi.
I am plotting a system (compound microscope), and want to zoom in onto some parts.
I tried plt.xlim plt.ylim but they have no effect.
Any idea how I can do it?
Thanks.
Petro.

[mjhoptics]

Hello @khoroshyy,
There are a couple of ways, depending on the environment you're using. If you use jupyter notebooks, you can use the matplotlib interactive widget mode and get a zoom box functionality using that.

Start your file with:
%matplotlib widget

When you then create a lens layout and mouse over the figure, you get icons in the upper left corner, including one for a zoom box.

If this environment isn't available to you, you can manipulate the figure bounding box through the InteractiveFigure api. Here is a notebook to demonstrate the options.

Zoom example - Telescope with reducer

Use interactive matplotlib figures

# use widget to enable interactive figures.
%matplotlib widget

from rayoptics.environment import *

isdark = False

opm = OpticalModel()
opm['system_spec'].title = 'RC w/0.75x reducer, 200mm, f/8, Fig 14.11'
sm  = opm['seq_model']
osp = opm['optical_spec']
pm = opm['parax_model']
em = opm['ele_model']
pt = opm['part_tree']

### Define first order aperture and field for system

osp['pupil'] = PupilSpec(osp, key=['object', 'epd'], value=200.0)
osp['fov'] = FieldSpec(osp, key=['object', 'angle'], value=0.75, flds=[0., .707, 1.], is_relative=True)
osp['wvls'] = WvlSpec([('F', 0.5), ('d', 1.0), ('C', 0.5)], ref_wl=1)

### Define interface and gap data for the sequential model

opm.radius_mode = True
sm.do_apertures = False

sm.gaps[0].thi=1e10

sm.add_surface([-1200, -395.4545, 'REFL', '', 100.055])
sm.ifcs[sm.cur_surface].profile = Conic(r=-1200, cc=-1.146871)
sm.add_surface([-654.5455, 395.4545, 'REFL', '', 78.83/2])
sm.ifcs[sm.cur_surface].profile = Conic(r=-654.5455, cc=-6.606556)
sm.add_surface([0, 7.968605], sd=30)
sm.ifcs[sm.cur_surface].interact_mode = 'dummy'
sm.add_surface([44.70335, 7, 'N-BK7', 'Schott', 23])
sm.add_surface([58.1758, 6, 'F2', 'Schott', 23])
sm.add_surface([38.91634, 5.316244, '', '', 23])
sm.add_surface([99.03769, 7, 'N-BK7', 'Schott', 23])
sm.add_surface([234.9394, 80, '', '', 23])

### Update the model

opm.update_model()

## add a hole to the primary mirror

M1 = pt.obj_by_name('M1')
M1.hole_sd = 30.0
opm.update_model()

## create assemblies for the OTA and the reducer

opm.add_assembly_from_seq(1, 3, label='R-C Telescope')
opm.add_assembly_from_seq(4, 8, label='Reducer')
opm.update_model()

## set the image at the paraxial focus

pimd = -pm.ax[-2][mc.ht]/pm.ax[-1][mc.slp]
sm.gaps[-1].thi = pimd
opm.update_model()

set_vignetting(opm)

layout_plt = plt.figure(FigureClass=InteractiveLayout, opt_model=opm, is_dark=False).plot()

Zooming by setting the view_bbox

This is the brute force way to zoom into the model. The view_bbox coordinates are expressed in model global coordinates. There are no rotations in this exmple. The element semi-diameters can be obtained using sm.list_model(). The surface interface global coordinates can be obtained using list_gbl_tfrms()

sm.list_model()

              r            t        medium     mode   zdr      sd
  Obj:     0.000000  1.00000e+10       air      dummy  1      1.0000
    1: -1200.000000     -395.454       air    reflect -1      100.06
    2:  -654.545500      395.454       air    reflect  1      39.415
    3:     0.000000      7.96861       air      dummy  1      30.000
    4:    44.703350      7.00000     N-BK7             1      23.000
    5:    58.175800      6.00000        F2             1      23.000
    6:    38.916340      5.31624       air             1      23.000
    7:    99.037690      7.00000     N-BK7             1      23.000
    8:   234.939400      80.0930       air             1      23.000
  Img:     0.000000      0.00000                dummy  1      1.0000

sm.list_gbl_tfrms('t')

 0:       0.00000       0.00000  -10000000000.00000
 1:       0.00000       0.00000       0.00000
 2:       0.00000       0.00000    -395.45450
 3:       0.00000       0.00000       0.00000
 4:       0.00000       0.00000       7.96861
 5:       0.00000       0.00000      14.96861
 6:       0.00000       0.00000      20.96861
 7:       0.00000       0.00000      26.28485
 8:       0.00000       0.00000      33.28485
 9:       0.00000       0.00000     113.37790

The bounding box is set on the InteractiveLayout

The bounding box is defined with the lower left and upper right corner coordinates being specified

layout_plt.set_view_bbox([[0, -25], [35, 25]])
layout_plt.plot()

You can also set the bounding box in the Figure constructor.

layout_plt1 = plt.figure(FigureClass=InteractiveLayout, opt_model=opm, is_dark=False, view_bbox=[[0, -25], [35, 25]]).plot()

If you have any suggestions to make this easier to do in a scripting environment, like specifying a range of surfaces, please let me know.

Thanks

Mike Hayford