Package xal.model.elem

Class ThinLens

java.lang.Object

xal.model.elem.Element

xal.model.elem.ThinElement

xal.model.elem.ThinLens

All Implemented Interfaces:

IComponent, IElement

public class ThinLens
extends ThinElement

Represents a thin lens abstract modeling element in a particle beam transport/accelerator system.

A zero value for focal length indicates zero focusing strength, or infinite focal length. Positive focal lengths imply focusing while negative values imply defocusing.

Author:

Christopher K. Allen

Field Summary

Fields

Modifier and Type	Field	Description
static final String	TYPE	string type identifier for all ThinLens objects

Fields inherited from class xal.model.elem.Element

dblNodeLen, dblNodePos

Fields inherited from interface xal.model.IElement

LIGHT_SPEED, PERMEABILITY, PERMITTIVITY, UNIT_CHARGE

Constructor Summary

Constructors

Constructor	Description
ThinLens()	JavaBean Constructor - creates a new uninitialized instance of ThinLens BE CAREFUL
ThinLens(String strId, double dblFx, double dblFy, double dblFz)	Creates a new instance of ThinLens A zero value for focal length indicates zero focusing strength, or infinite focal length.

Method Summary

Modifier and Type	Method	Description
double	elapsedTime(IProbe probe)	Returns the time taken for the probe to propagate through element.
double	energyGain(IProbe probe)	Returns zero for the energy gain imparted to any probe by a thin lens.
void	print(PrintWriter os)	Dump current state and content to output stream.
void	setFocalLengthX(double dblFx)	Set the focal length in the x direction.
void	setFocalLengthY(double dblFy)	Set the focal length in the y direction.
void	setFocalLengthZ(double dblFz)	Set the focal length in the z direction.
protected PhaseMap	transferMap(IProbe probe)	Compute and return the block-diagonal transfer matrix representing a thin lens in each phase plane.

Methods inherited from class xal.model.elem.ThinElement

applyErrors, elapsedTime, energyGain, getLength, longitudinalPhaseAdvance, longitudinalPhaseAdvance, transferMap

Methods inherited from class xal.model.elem.Element

addCloseElements, backPropagate, backPropagate, compDriftingTime, compProbeLocation, getAlignX, getAlignY, getAlignZ, getCloseElements, getHardwareNodeId, getId, getLatticePosition, getNodeLen, getNodePos, getParent, getPhiX, getPhiY, getPhiZ, getPosition, getType, getUID, initializeFrom, propagate, propagate, setAlign, setAlignX, setAlignY, setAlignZ, setHardwareNodeId, setId, setParent, setPhiX, setPhiY, setPhiZ, setPosition, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

TYPE

public static final String TYPE

string type identifier for all ThinLens objects

See Also:

• Constant Field Values

Constructor Details

ThinLens

public ThinLens(String strId,
 double dblFx,
 double dblFy,
 double dblFz)

Creates a new instance of ThinLens A zero value for focal length indicates zero focusing strength, or infinite focal length. Positive focal lengths imply focusing while negative values imply defocusing.

Parameters:

strId - string identifier of element

dblFx - focal length in the x phase plane (in meters)

dblFy - focal length in the y phase plane (in meters)

dblFz - focal length in the z phase plane (in meters)

ThinLens

public ThinLens()

JavaBean Constructor - creates a new uninitialized instance of ThinLens BE CAREFUL

Method Details

setFocalLengthX

public void setFocalLengthX(double dblFx)

Set the focal length in the x direction.

Parameters:

dblFx - focal length in the x phase plane (in meters)

setFocalLengthY

public void setFocalLengthY(double dblFy)

Set the focal length in the y direction.

Parameters:

dblFy - focal length in the y phase plane (in meters)

setFocalLengthZ

public void setFocalLengthZ(double dblFz)

Set the focal length in the z direction.

Parameters:

dblFz - focal length in the z phase plane (in meters)

elapsedTime

public double elapsedTime(IProbe probe)

Returns the time taken for the probe to propagate through element.

Specified by:

elapsedTime in class ThinElement

Parameters:

probe - propagating probe

Returns:

the value zero

energyGain

public double energyGain(IProbe probe)

Returns zero for the energy gain imparted to any probe by a thin lens.

Specified by:

energyGain in class ThinElement

Parameters:

probe - dummy argument

Returns:

a value of zero

transferMap

protected PhaseMap transferMap(IProbe probe)
                        throws ModelException

Compute and return the block-diagonal transfer matrix representing a thin lens in each phase plane.

Specified by:

transferMap in class ThinElement

Parameters:

probe - dummy argument, no probe parameters are used

Returns:

the block diagonal transfer matrix

Throws:

ModelException - this should not occur

print

public void print(PrintWriter os)

Dump current state and content to output stream.

Overrides:

print in class Element

Parameters:

os - output stream object