addRefractiveSurface

R2026b

Add refractive surface component to optical system

Since R2026a

Syntax

addRefractiveSurface(opsys)

addRefractiveSurface(opsys,Name=Value)

Description

Add-On Required: This feature requires the Optical Design and Simulation Library for Image Processing Toolbox add-on.

addRefractiveSurface(opsys) adds a default circular refractive surface to the optical system opsys. When you create a surface using this function, you create a Surface object. You must add at least two refractive surfaces for a lens component before this function adds them to the optical system. To complete a component, you must add a closing surface with an unspecified or ambient Material value.

addRefractiveSurface(opsys,Name=Value) specifies properties of the refractive surface using one or more name-value arguments. For example, addRefractiveSurface(Radius=-50) specifies the radius of curvature of the surface as -50, in millimeters.

Examples

Create Convex Singlet Lens

Create an empty optical system.

opsys = opticalSystem(Name="Convex Singlet");

To add a lens component to the optical system, create the first refractive surface of the lens. Specify a positive radius of curvature using the Radius name-value argument, the thickness of the lens using the DistanceToNext name-value argument, and the glass material type using the Material name-value argument.

addRefractiveSurface(opsys,Radius=10,DistanceToNext=4,Material="N-BK7")

Create the second refractive surface of the lens. This exit surface is the outside surface of the lens that contacts the ambient material. To create a convex lens, specify a negative radius of curvature for the second surface using the Radius name-value argument.

addRefractiveSurface(opsys,Radius=-10)

Display the first Surface object created by the addRefractiveSurface object function.

opsys.Surfaces(1)

ans = 
  Surface with properties:

                   Name: [0×0 string]
                  Shape: [1×1 optics.shape.Circular]
                 Radius: 10
          ConicConstant: 0
    NormalizationRadius: 1
              Aspherics: [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
          EvenAspherics: [0 0 0 0 0 0 0 0 0 0]
                Coating: [0×0 opticalCoating]
                   Grid: []
              GridXLims: []
              GridYLims: []
               Position: [0 0 0]
             TiltAngles: [0 0 0]

Display the LensElement object, which represents the lens component, created by the addRefractiveSurface object function. The Surfaces property of this object specifies the two surfaces.

opsys.Components(1)

ans = 
  LensElement with properties:

          Name: [0×0 string]
     Materials: [1×1 opticalMaterial]
     Thickness: 4
      Surfaces: [1×2 optics.surface.Surface]
         Shape: [1×2 optics.shape.Circular]
      Coatings: [0×0 opticalCoating]
      Position: [0 0 0]
    TiltAngles: [0 0 0]

Display a 2-D visualization of the optical system using the view2d function.

view2d(opsys)

ans = 
  OpticalSystemViewer2D with properties:

            Title: ""
    OpticalSystem: [1×1 opticalSystem]
           Labels: "none"
      FieldPoints: "on"
             Rays: [0×0 optics.ui.Rays2D]
           Parent: [1×1 Figure]

  Show all properties

Create Aspheric Lens

Create an empty optical system.

opsys = opticalSystem(Name="Aspheric Lens");

Create the first aspheric surface, and specify the even aspheric coefficients using the EvenAspherics name-value argument. Specify the conic shape of the lens as parabolic using the ConicConstant name-value argument. Specify the surface semi-diameter using the SemiDiameter name-value argument, and specify the refractive index as 1.545 and the Abbe number as 56 using the Material name-value argument. Specify the lens thickness as 2.5 millimeters using the DistanceToNext name-value argument.

addRefractiveSurface(opsys,Radius=1.7349, ...
EvenAspherics=[0 -3.35772e-1 9.43709e-2 5.16187e-2 -7.01966e-2 3.50377e-2 -9.52759e-3 1.47430e-3 -1.21780e-4 4.16141e-6], ...
ConicConstant=-1,SemiDiameter=1.6,Material=[1.545 56],DistanceToNext=2.5)

Create the second aspheric surface, and specify the even aspheric coefficients using the EvenAspherics name-value argument.

addRefractiveSurface(opsys,Radius=1.0513, ...
EvenAspherics=[0 -4.10700e-1 2.52834e-1 -1.22801e-1 4.26734e-2 -1.02969e-2 1.69864e-3 -1.83493e-4 1.16681e-5 -3.29217e-7], ...
ConicConstant=-1,SemiDiameter=1)

Display a 2-D visualization of the aspheric lens using the view2d function.

view2d(opsys)

ans = 
  OpticalSystemViewer2D with properties:

            Title: ""
    OpticalSystem: [1×1 opticalSystem]
           Labels: "none"
      FieldPoints: "on"
             Rays: [0×0 optics.ui.Rays2D]
           Parent: [1×1 Figure]

  Show all properties

Input Arguments

opsys — Optical system

opticalSystem object

Optical system to which to add the refractive surface, specified as an opticalSystem object.

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Example: addRefractiveSurface(Radius=-50) specifies the radius of curvature of the refractive surface as -50, in millimeters.

Material — Glass material of refractive surface

string scalar | character vector | opticalMaterial object | 2-element row vector

Glass material of the refractive surface, specified as one of these values:

Material Value	Description
string scalar or character vector	Specify the name of a glass material. For example, specify Material as "N-SF6HT" to assign a glass material from the Schott catalog to the refractive surface. Tip To search for a material in the default glass library, use the searchGlassLibrary function. To query the properties of a material using its name, use the pickGlass function. To add a glass catalog containing a new glass material to the glass library, use the addGlassCatalog object function.
opticalMaterial object	Specify a custom material by configuring the properties of an opticalMaterial object.
2-element row vector	Index of refraction and Abbe number of the glass material, specified as a 2-element row vector of the form [Nd Vd], where Nd and Vd are the index of refraction and Abbe number, respectively.

When you specify one or more refractive surfaces with a non-ambient material, such as the surface of a lens, you must add a second, closing refractive surface with Material unspecified, or specified as the value of the AmbientMaterial property of the optical system opsys.

For example, to create a singlet lens that contains two surfaces, you must specify the Material value only for the first surface.

DistanceToNext — Distance to next surface

0 (default) | positive scalar

Distance to the next surface, in millimeters, specified as a positive scalar. For the first surface you create, specify DistanceToNext to set the lens thickness.

For the second surface you create, specify DistanceToNext to set the gap width to the next surface or component that is added to the optical system.

Note

You must specify DistanceToNext as a nonzero value for any surface with a non-ambient material property, except the entrance surface. If required for your application, the entrance surface of an optical system can have zero thickness.

Coating — Surface optical coating

opticalCoating object

Surface optical coating, specified as an opticalCoating object. The addRefractiveSurface function applies the coating to the front of the surface where incident rays hit. If the surface is followed by an ambient material, the addRefractiveSurface function applies the coating to the back of the surface.

Radius — Radius of curvature

0 (default) | numeric scalar | 2-element row vector

Radius of curvature of the refractive surface, specified as one of these options:

• Numeric scalar — The radius of curvature applies in both the x- and y-directions.

• 2-element row vector — Specifies the radius of curvature for a biconic surface, in the form [R_x, R_y], where R_x and R_y are the radii of curvature in the x- and y-directions, respectively.

For a set of two refractive surfaces, such as the opposite surfaces of a lens component, specify the Radius of the refractive surface based on these criteria.

First refractive surface (R₁) — Specify a positive Radius value for the first surface (facing the light source) if the center of curvature is on the same side as the incoming light, and a negative Radius value if it is on the opposite side.

Second refractive surface (R₂) — Specify a positive Radius value for the second surface (facing away from the light source) if the center of curvature is on the opposite side of the incoming light, and a negative Radius value if it is on the same side.

SemiDiameter — Surface semi-diameter

5 (default) | positive scalar

Surface semi-diameter, specified as a positive scalar. The semi-diameter is the distance, along the positive y-axis, from the center of the optical surface to the edge of the usable optical area, describing the aperture through which light enters. This quantity is half the full diameter of the surface or aperture through which light can pass. By default, the surface is circular with a semi-diameter of 5.

Note

For a rectangular surface, use the RectangleSize name-value argument to specify the surface size, instead.

RectangleSize — Rectangular surface size

2-element row vector

Rectangular surface size of the aperture through which light can pass, specified as a 2-element row vector. The vector is of the form [Width Height], where Width and Height are the width and height of the rectangular surface, respectively. By default, the surface is circular with a semi-diameter of 5.

Note

For a circular surface, use the SemiDiameter name-value argument to specify the surface size, instead.

Aspherics — Aspheric coefficients

zeros(1,20) (default) | 20-element row vector

Aspheric coefficients of the refractive surface, specified as a 20-element row vector. The aspheric coefficients describe the aspheric profile of the refractive surface. By default, both the even-powered and odd-powered aspheric coefficients are equal to zero, and the aspheric surface is a purely conic section without any higher-order deviations. The conic surface shape depends on the magnitude and sign of the conic constant specified by the ConicConstant name-value argument.

EvenAspherics — Even-powered aspheric coefficients

zeros(1,10) (default) | 10-element row vector

Even-powered aspheric coefficients of the refractive surface, specified as a 10-element row vector.

ConicConstant — Conic constant

0 (default) | numeric scalar | 2-element row vector

Conic constant that defines the conic shape of the aspheric surface profile, specified as one of these options:

• Numeric scalar — The conic constant applies in both the x- and y-directions.

• 2-element row vector — Specifies the conic constant for a biconic surface, in the form [K_x, K_y], where K_x and K_y are the conic constants in the x- and y-directions, respectively.

Depending on the value of the conic constant K, the aspheric surface has these conic shapes. For a biconic surface, the conic shape in each direction is determined independently by the corresponding element of ConicConstant.

ConicConstant (K) Value	Conic Shape
K = 0	Sphere
K in range [-1,0]	Ellipse
K = -1	Parabola
K in range [-inf,-1]	Hyperbola

NormalizationRadius — Normalization radius

1 (default) | positive scalar

Normalization radius, specified as a positive scalar. The addRefractiveSurface function uses the normalization radius to non-dimensionalize the higher-order terms in the polynomial describing the aspheric surface.

Tip

To represent the maximum radial extent of the aspheric surface as the semi-diameter, specify the normalization radius as equal to the value of the SemiDiameter name-value argument.

Tip

If the surface curvature is a factor and aspheric deviations are relatively small compared to the overall curvature, you can specify the normalization radius as the base radius of curvature (the radius of the best-fit sphere to the aspheric surface).

Name — Name of refractive surface

[] (default) | string scalar | character vector

Name of refractive surface, specified as a string scalar or character vector.

Grid — Additional Z-sag values on the regular grid

[] (default) | M-by-N matrix

Additional Z-sag values on the regular grid, specified as an M-by-N matrix. Units are in millimeters. M is the number of y samples spanning GridYLims, and N is the number of x samples spanning GridXLims.

The addRefractiveSurface function adds these grid values to the existing surface sag value. Positive values move the surface toward the positive z direction and negative values move the surface toward the negative z direction from the baseline that the function computes using the Radius, ConicConstant, and aspheric term arguments in local surface coordinates. The function interpolates grid values using bicubic interpolation and extrapolates values near the edges.

The element Grid(1,1) corresponds to the corner at (GridYLims(1), GridXLims(1)), which is the minimum y- and minimum x-position of the grid. The element Grid(1,end) corresponds to (GridYLims(1), GridXLims(2)), and Grid(end,end) corresponds to (GridYLims(2), GridXLims(2)), which is the maximum y- and maximum x-position of the grid. Row index increases with y, and column index increases with x.

Data Types: double

GridXLims — X-limits of grid edges

2-element row vector

X-limits of the grid edges in local surface coordinates, specified as a 2-element row vector. Units are in millimeters. The vector is of the form [x_min x_max], where x_min and x_max are the minimum and maximum x-coordinates of the grid, respectively. The second element must be greater than the first.

By default, the limits are [–sd sd] for circular shapes and [–w/2 w/2] for rectangular shapes, where sd is the semi-diameter and w is the width of the rectangular surface. The function ignores grid values that extend outside the surface shape. Valid regions of the surface not included in these limits use a grid value of 0.

Data Types: double

GridYLims — Y-limits of grid edges

2-element row vector

Y-limits of the grid edges in local surface coordinates, specified as a 2-element row vector. Units are in millimeters. The vector is of the form [y_min y_max], where y_min and y_max are the minimum and maximum y-coordinates of the grid, respectively. The second element must be greater than the first.

By default, the limits are [–sd sd] for circular shapes and [–h/2 h/2] for rectangular shapes, where sd is the semi-diameter and h is the height of the rectangular surface. The function ignores grid values that extend outside the surface shape. Valid regions of the surface not included in these limits use a grid value of 0.

Data Types: double

Version History

Introduced in R2026a

R2026b: Specify biconic surface properties

You can now specify separate radii of curvature and conic constants in the x- and y-directions to create biconic surfaces by using the Radius and ConicConstant name-value arguments.

R2026b: Specify grid sag values for surface

You can now specify additional Z-sag values on a regular grid to add to the surface sag baseline by using the Grid, GridXLims, and GridYLims name-value arguments.