This java applet is a simulation that demonstrates
magnetostatics and electromagnetic waves in two dimensions.
When the applet starts up you will see a white circle (called the
"source") emitting red and green circular waves. The color indicates the
electric field; green areas are positive (towards you) and the red areas
are negative (away from you). (In this applet, the electric field is
always perpendicular to the plane of the screen; that means there are no
free charges, and all currents have to be perpendicular to the screen as
well. It also means the electrostatic potential is zero everywhere.)
In addition to the red and green color, you will see arrows which
indicate the direction of the magnetic field (which is always in the plane
of the screen).
Also, sources and conductors may show a blue or yellow color,
indicating current. Yellow means that current is flowing towards you and
blue means it is flowing away from you.
Conductors, dielectrics, and other media will show up as gray. There
aren't enough colors or shades of gray to make the different kinds of
media look different. Use the Show Material Type menu option to
tell them apart.
These are electromagnetic waves, so in real life they would be moving
at the speed of light.
This is the TM version of the applet. There is also a TE version.
The Setup popup can be used to view some interesting pre-defined
experiments. Once an experiment is selected, you may modify it all you
want. The choices are:
- Single Source: this is a single wire with an alternating
current, creating circular waves.
- Two Sources: this is two wires emitting circular waves,
creating an interference pattern between them.
- Plane Wave: this demonstrates a simple plane wave source.
- Intersecting Planes: this demonstrates two plane waves
intersecting at right angles.
The following 28 setups are all static, involving steady currents or
permanent magnets, with no waves (except at the start). When you select
one of them, just wait a bit for the system to reach a steady state.
- Single Wire: this is a wire with a steady current.
- Wire Pair: this is two wires with current in the same
direction.
- Dipole Wire Pair: this is two wires with current in opposite
directions.
- Magnet Pair: this is two permanent magnets with the north
poles facing up.
- Magnet Pair, Opp: this is two permanent magnets; the left one
has the north pole facing up and the right one has it facing down.
- Magnet Pair Stacked: this is two permanent magnets stacked on
top of each other with the north poles facing up.
- Magnet Pair Stacked Opp: this is two permanent magnets
stacked on top of each other with the north poles facing towards each
other.
- Uniform Field: this is a (fairly) uniform field created by
currents on the left and right sides of the screen.
- Field Near Aperture: this shows a uniform magnetic field
leaking through an aperture in a perfect conductor.
- Solenoid: this shows the cross section of a coil of wire with
a current running through it.
- Toroidal Solenoid: this shows the cross section of a torus
(donut) with a coil of wire wrapped around it.
- Sphere: this shows the cross section of a uniformly
magnetized sphere (actually an infinitely long cylinder, since this is
2-D).
- Thick Wire: this shows a thick wire carrying a current.
- Hole in Wire 1: this shows a thick current-carrying wire with
a hole in it, resulting in no field in the hole.
- Hole in Wire 2: this shows a thick current-carrying wire with
an off-center hole in it, resulting in a uniform field in the hole.
- Ferromagnet: this is a ferromagnet (like soft iron) near a solenoid. The
ferromagnets in this applet are linear and have no hysteresis.
- Diamagnet: this is a strong diamagnet near a solenoid. The diamagnets in this
applet are far stronger than any known diamagnet, to illustrate the
effect more clearly.
- Meissner Effect: this shows a superconductor near
a solenoid. The superconductor rejects all magnetic fields (except at
the surface). The blue and yellow color in the superconductor indicates
the presence of eddy currents. Since this is a superconductor, the eddy
currents do not die out.
- Horseshoe Magnet: this shows an electromagnet in the shape of
a horseshoe.
- Horseshoe + Load: this shows a horseshoe electromagnet
carrying a ferromagnetic load.
- Magnetic Shielding 1: this shows the magnetic field of
solenoid being shielded by a ferromagnet. Notice that there is very
little field below the ferromagnet. (You will see a somewhat strong
magnetic field one grid square below the ferromagnet, but that is a bug
and this would not happen in real life.)
- Magnetic Shielding 2: this shows the magnetic field of
solenoid being shielded by a ferromagnetic box. Notice that there is
very little field outside of the ferromagnet. The ferromagnet is
conducting and thus will reflect the wave generated when the current is
first switched on in the solenoid; so you will have to wait a bit for
the oscillation to die out.
- Magnetic Shielding 3: this shows the magnetic field of
solenoid being shielded by a ferromagnetic sphere. The field is weaker
outside of the ferromagnet; the brightness is turned up so that you can
see that the field outside looks like the field of a magnetic dipole
(compare it to Dipole Wire Pair and Sphere). You will have
to wait even longer for the oscillation to die out because the
brightness is turned up and the current is much stronger than in the
previous setup.
- Magnetic Shielding 4: this shows a ferromagnetic box
shielding its interior from a uniform external field.
- Magnetic Circuit 1: this shows a magnetic circuit; the field
generated by the solenoid on the right is being "conducted" by
ferromagnetic material.
- Magnetic Circuit 2: this shows a magnetic circuit with an air
gap on the left.
- Monopole Attempt: This is a simulation of what would happen
if you tried to make a magnetic monopole (a magnet with only a north
pole and no south pole) by taking a bunch of magnets and forcing them
into a square with their south poles in the center. Instead of getting a
monopole, you would find that the gaps between the magnets would act as
south poles, and the field there would be much stronger than on the
faces of the magnets. If you could force them together perfectly with no
gaps, there would be no field at all anywhere because all the currents
would cancel out.
- Quadrupole Lens: this shows four magnets in the
shape of hyperbolas, forced together. This device is used to focus
particle beams.
- Halbach Array: this shows five magnets in a linear
Halbach array. The magnetic field is concentrated on the bottom side. To
see the orientations of the individual magnets, select Show
Magnetization from the Show popup.
- Halbach Array (long): this shows a longer Halbach array.
- Halbach Array (dipole): this shows a circular Halbach
array with a uniform magnetic field inside.
- Halbach Array (quadrupole): this shows a circular Halbach
array with a magnetic quadrupole inside.
The rest of the setups are all dynamic, involving changing currents
and waves.
- Dielectric: this shows wave packets being reflected by a
dielectric medium. Waves travel slower in a dielectric, causing the
incoming wave to be partially reflected and partially refracted.
- Fair Conductor Reflection: this shows wave packets being
reflected by a fairly good conductor. When waves hit a conductor, it
causes eddy currents which cause the wave to be mostly reflected. A
small fraction of the wave is transmitted, and that part is attenuated
almost immediately.
- Poor Conductor Reflection: this shows wave packets being
reflected by a poor conductor. When waves hit the conductor, it causes
weak eddy currents which cause the wave to be partly reflected. Part of
the wave is transmitted, and that part is quickly attenuated by eddy
currents.
- Skin Effect 1: this shows that waves hitting a conductor will
only penetrate a certain distance, called the skin
depth. (Actually the strength of the wave falls off exponentially,
but the skin depth is a measure of how fast this happens.)
- Skin Effect 2: this shows that the skin depth is smaller for
higher-frequency waves.
- Resonant Absorption: this creates a medium made up of little
resonators. The resonators have a characteristic frequency which is the
same as the frequency of the incoming radiation. Since this medium has a
resonance frequency, it is dispersive, which means that waves of
different frequencies travel at different speeds. Here, since the
incoming radiation's frequency is close to the resonance frequency, it
is absorbed by the medium, although much of it is reflected because of
the discontinuity caused by the strong absorption.
- Dispersion 1: this setup illustrates dispersion in the
resonant medium. The incident wave has a frequency which is much lower
than the resonance frequency, so the refractive index is only slightly
higher than 1. So it is transmitted largely without reflection.
- Dispersion 2: Here the incident wave has a frequency which is
slightly lower than the resonance frequency, so waves travel much more
slowly in the medium, and more of the wave is reflected. Also there is
some absorption, so the farther the wave travels into the medium, the
weaker it is.
- Dispersion 3: Here the incident wave has a frequency which is
slightly higher than the resonance frequency, so waves have a phase
velocity that is faster than in a vacuum. So waves seem to move faster
than the speed of light in a vacuum. Still, the signal velocity in the
medium is not faster than the speed of light; when the source is first
switched on, the initial wave train travels at normal speed.
- Dispersion 4: Here the incident wave has a frequency which is
much higher than the resonance frequency, so waves have a phase velocity
that is only slightly faster than in a vacuum. So the medium has very
little affect on the incoming wave.
- Magnetic Diffusion: this shows a magnetic field (generated by
a wire) diffusing slowly through a conductor. Wait for the field to
slowly build up, then get rid of the wire (the yellow square) by
clicking on it. The field will slowly die out; the presence of the
conductor causes changes in magnetic field to diffuse slowly rather than
happening at the speed of light.
- Oscillating Ring: this shows the cross section of a ring with
an oscillating current running through it. This is approximated by two
wires with current running in opposite directions. The oscillating
current causes radiation; this is called magnetic dipole radiation.
- Oscillating Ring Pair: this shows the cross section of two
rings with an oscillating current running through them in opposite
directions, resulting in magnetic quadrupole radiation.
- Ring Induction: this shows a ring with an oscillating current
running through it, inducing an opposing current in another ring right
below it.
- Wire Induction: this shows a wire with an oscillating current
running through it, inducing an opposing current in another wire right
below it.
- Ring + Fair Conductor: this shows a ring with a slowly
oscillating current running through it, with a fairly good conductor
underneath it. The changing current generates eddy currents in the
conductor, causing the magnetic field to diffuse slowly through the
conductor to the other side.
- Ring + Poor Conductor: this shows a ring with a slowly
oscillating current running through it, with a poor conductor underneath
it. The eddy currents are much weaker, so the magnetic field diffuses
quickly through the conductor to the other side.
- Wire + Fair Conductor: this shows a wire with a slowly
oscillating current running through it, with a fairly good conductor
underneath it. The changing current generates eddy currents in the
conductor, causing the magnetic field to diffuse slowly through the
conductor to the other side.
- Wire + Poor Conductor: this shows a wire with a slowly
oscillating current running through it, with a poor conductor underneath
it. The eddy currents are much weaker, so the magnetic field diffuses
quickly through the conductor to the other side.
- Rings + Ferromagnet: this is an oscillating ring (in the
middle) positioned near two conducting rings. There is a ferromagnetic
core present which cause the induced current to be stronger in the lower
ring than in the upper ring.
- Osc. Solenoid: this is a solenoid with an oscillating current
running through it.
- Transformer: this is two coils wrapped around each other,
with an oscillating current in the inner one. This induces a current in
the outer one. This transformer is rather pointless since the number of
turns is the same in the inner and outer coils. This applet cannot
demonstrate transformers very well because there is no way to measure
voltage, and because the current is always perpendicular to the screen,
and none of the conducting grid squares are connected to one another.
Also the current in the inner coil is fixed and is not affected by the
outer coil.
- Osc. Toroidal Solenoid: this is a toroidal solenoid with an
oscillating current running through it.
- Coaxial Cable: this is a cross section of a coaxial cable,
with an oscillating current running through it. Note that there is very
little radiation (assuming the wavelength of the oscillation is small
compared to the diameter of the cable). This is part of the reason that
coaxial cable is used to carry high frequencies--it reduces the amount
of power loss from radiation.
- Cond. in Osc. Field: this is a small conducting square in a
uniform field that is oscillating.
- Moving Wire: this is a current-carrying wire which is moving
at a significant fraction of the speed of light. The magnetic field
lines are slightly flattened out. It stops periodically and then starts
again so you can see the radiation generated when its velocity changes.
- Moving Wire in Tube: this is a current-carrying wire which is
moving through a conducting tube. When the wire moves it causes a
changing magnetic field, which generates eddy currents in the tube. The
presence of the tube causes a force on the wire opposing the direction
of motion, which you can see by selecting Show Force from the
Show menu.
- Moving Magnet in Tube: this is a magnet which is moving through a conducting tube. When the magnet
moves it causes a changing magnetic field, which generates eddy currents
in the tube. The presence of the tube causes a force on the magnet
opposing the direction of motion, which you can see by selecting Show
Force from the Show menu. The magnet stops periodically to
give the eddy currents a chance to die out.
- Rotating Magnet 1: this is a rotating magnet, which emits
radiation. Select Show Magnetization to see the direction the
magnet is pointing.
- Rotating Magnet 2: this is a magnet which rotates through 180
degrees and then reverses direction. This causes it to emit radiation.
- Scattering 1: this shows a plane wave being scattered by a
small resonator. The incoming plane wave gets turned off periodically so
you can see the scattered wave better. The frequency of the incoming
wave is close to the resonant frequency of the resonator, so the
scattered wave is relatively strong.
- Scattering 2: Here the frequency of the incoming wave is not
as close to the resonant frequency of the resonator, so the scattered
wave is much weaker.
- Big TM11 Mode: this creates a small superconducting cavity
with a standing wave inside it. The electric field is 90 degrees out of
phase with the magnetic field. The field in the cavity is oscillating in
its TM11 mode.
- TM11 Modes: this creates a set of small superconducting
cavities with TM11 standing waves inside them.
- TMn1 Modes: this creates a set of small superconducting
cavities with TM11, TM21, and TM31 standing waves inside them. (If the
resolution is set higher then more cavities are present with higher
modes.)
- TMnn Modes: this creates a set of small superconducting
cavities with various TM modes inside them.
- TMn1 Mode Combos: this creates a set of small superconducting
cavities, with various combinations of TMn1 modes inside them.
- TMnn Mode Combos: this creates a set of small superconducting
cavities, with various combinations of TM modes inside them.
- Triangle Modes: this creates a set of small triangular
cavities with standing waves.
- Circular Modes 1: this creates a set of small circular
cavities with standing waves.
- Circular Modes 2: this creates a circular cavity with two
standing waves superimposed 90 degrees out of phase so that the fields
appear to rotate.
- Waveguides 1: This creates a series of waveguides of different widths. Narrower waveguides,
like at the left end of the screen, have higher cutoff frequencies.
Notice that the waves seem to be moving faster in thinner waveguides.
They appear to be moving faster than waves normally move in the applet.
This is because the phase velocity is faster in thinner waveguides; but
the signal velocity is actually slower than normal, as you can verify by
clicking the Clear Waves button and watching the wave move down
the guide for the first time.
Since the waveguides are being driven by a plane wave, only the TE01
mode is present. (See the waveguide
applet for another way to view waveguide modes.)
- Waveguides 2: This is just the same set of waveguides with a
lower frequency. The waveguide on the left has a cutoff frequency that
is higher than the source, so there is no wave motion in it. You can fix
this by turning the Source Frequency slider up.
- Waveguides 3: This is a set of identical waveguides being
driven by small holes at different locations. This causes different sets
of modes to be excited in different proportions. When the guide is being
driven near the center, the TE01 mode is dominant, but when it is driven
near the edge, the TE02 mode is more prevalent. The frequency is low
enough so that all other modes are cut off. You can fix this by turning
the frequency up. By turning the frequency down, you can cut off the
TE02 mode as well.
- Waveguides 4: This is a set of identical waveguides with
various modes present. The first waveguide contains the TE01 mode; the
second contains the TE02 mode; the third contains the TE03 mode; the
fourth contains TE01 and TE02; the fifth contains TE01 and TE03; the
sixth contains TE02 and TE03. (There will not be room on your screen for
all these modes if your resolution is not set high enough.)
Notice that the higher modes (TE02 and especially TE03) seem to be
moving faster. This is because the phase velocity of TE02 and TE03 is
greater than that of TE01. Their signal velocities are slower, though,
which is why it takes the TE03 wave so long to make it down to the end
of the waveguide. Also if you turn off the source (by setting the source
popup to "No Sources") it will take quite a while for the TE03 mode to
stop.
- Resonant Cavities 1: This creates a series of rectangular
cavities being driven by a plane wave from above. As you change the
frequency you will see the response of each cavity change. Each cavity
has a different resonant frequency so it will respond differently. After
changing the frequency you may want to wait a bit for things to settle
down (or turn the simulation speed way up).
- Single Slit: this demonstrates diffraction of waves travelling through a slit.
- Double Slit: this demonstrates diffraction of waves
travelling through a double slit.
- Triple Slit.
- Obstacle: this demonstrates diffraction of waves travelling
around an obstacle.
- Half Plane: this demonstrates diffraction of waves around the
edge of a plane.
- Lloyd's Mirror: This shows an interferometer which consists
of a point source close to a mirror (at the bottom of the window). The
waves coming from the source interfere with the waves coming from its
mirror image.
The Source popup controls the wave sources (oscillating
currents). It has the following settings:
- No Sources: there will be no sources of wave motion.
- 1 Src, 1 Freq: there will be a single source of sinusoidal
waves at a single frequency (set using the Source Frequency
slider). This source can be dragged anywhere on the screen with the
mouse.
- 1 Src, 2 Freq: the source will be emitting two waves, at
separate frequencies. The first frequency is set using the Source
Frequency slider, and the second frequency is set using 2nd
Frequency.
- 2 Src, 1 Freq: two sources will be created, both at the same
frequency. But you can select the phase difference using the Phase
Difference slider. If the slider is all the way to the left, the
sources will be in phase; if it is all the way to the right, the sources
will be 180 degrees out of phase. (The top one will be green while the
bottom one is red, and vice versa.)
- 2 Src, 2 Freq: the two sources will be at different
frequencies. The Source 2 Frequency slider can be used to set the
second one's frequency.
- 3 Src, 1 Freq or 4 Src, 1 Freq: 3 or 4 sources will be
created, all at the same frequency.
- 1 Src, 1 Freq (Packet): the source will emit wave packets
periodically.
- x Plane Src, y Freq: the source(s) will emit plane waves rather than circular waves. The location
and direction of the plane wave can be modified by dragging one or both
of the two white circles. If the white circles are located at the edge
of the screen, the plane is extended offscreen; otherwise it is not.
Since the waves are not extended infinitely offscreen they are not true
plane waves, strictly speaking.
- 1 Plane 1 Freq (Packet): the source will emit plane wave
packets.
The Mouse popup controls what happens when the mouse is clicked.
The following settings are possible:
- Mouse = Add Perf. Conductor: Clicking on a point will create
a perfect conductor there. Clicking on an existing conductor will erase
it.
- Mouse = Add Good Conductor: Clicking on a point will create a
conductor which is not perfect but is still pretty good.
- Mouse = Add Fair Conductor: Clicking on a point will create a
fairly good conductor.
- Mouse = Add Current (+): Clicking on a point will create a
wire with current flowing in the positive z direction (towards you).
- Mouse = Add Current (-): Clicking on a point will create a
wire with current flowing in the negative z direction (away from you).
- Mouse = Add Ferromagnet: Clicking on a point will create a ferromagnetic medium. The ferromagnets in this applet
are linear and have no hysteresis (except for the permanent magnets).
- Mouse = Add Diamagnet: Clicking on a point will create a diamagnetic medium. The diamagnets in this applet are
far stronger than any known diamagnet, to illustrate the effect more
clearly.
- Mouse = Add Dielectric: Clicking on a point will create a
dielectric medium.
- Mouse = Add Magnet (Down/Up/Left/Right): Clicking on a point
will create a permanent magnet with the north pole pointing in the
direction indicated.
- Mouse = Add Resonant Medium: Clicking on a point will create
a resonant medium.
- Mouse = Clear: Clicking on a point will remove whatever is
there.
- Mouse = Adjust Conductivity: Clicking on a point and dragging
out a rectangular area will allow you to adjust the conductivity of the
conductors in that area using the Conductivity slider. The
Show Material Type menu option may come in handy here (and in the
following options) to see feedback from the changes you are making and
to compare the conductivity of all conductors on the screen.
- Mouse = Adjust Permeability: Clicking on a point and dragging
out a rectangular area will allow you to adjust the permeability of the
ferromagnets in that area using the Permeability slider.
- Mouse = Adjust Current: Clicking on a point and dragging out
a rectangular area will allow you to adjust the current flowing through
the wires in that area using the Current slider.
- Mouse = Adjust Dielectric: Clicking on a point and dragging
out a rectangular area will allow you to adjust the dielectric constant
on the dielectrics in that area using the Dielectric Constant
slider.
- Mouse = Adjust Mag Dir: Clicking on a point and dragging out
a rectangular area will allow you to adjust the direction of the
permanent magnets in that area using the Direction slider.
- Mouse = Adjust Mag Strength: Clicking on a point and dragging
out a rectangular area will allow you to adjust the strength of the
permanent magnets in that area using the Strength slider.
The Show popup determines which fields or other quantities to
display, and how to display them.
- Show Electric Field (E): Show the electric field as green
(positive, toward you) or red (negative, away from you).
- Show Magnetic Field (B): Show the magnetic field as arrows.
The arrows go from dark green to light green and then to white as the
field gets stronger.
- Show B Lines: Show the magnetic field as lines. The color of
the lines go from dark green to light green and then to white as the
field gets stronger. The density of the lines is kept fairly constant,
so in order to determine the field strength you need to look at the
color of the lines rather than how far apart they are.
- Show B Strength: Show the magnetic field strength using
shades of green.
- Show Current (j): Show the current density as yellow
(positive, toward you) or blue (negative, away from you).
- Show E/B: Show both the electric field and the magnetic field
arrows.
- Show E/B lines: Show both electric field and the magnetic
field lines.
- Show E/B/j: Show both the electric field and the magnetic
field arrows; in conductors, or where the current is nonzero, show the
current density instead of the electric field.
- Show E/B lines/j: Show both the electric field and the
magnetic field lines; in conductors, or where the current is nonzero,
show the current density instead of the electric field.
- Show Mag. Intensity (H): Show the magnetic intensity vector, which is equal to the
magnetic field minus the magnetization. In linear media (which, in this
applet, is everywhere except for inside permanent magnets) this is equal
to B divided by the permeability. This will be the same as
B unless ferromagnets, diamagnets, or permanent magnets are
present.
- Show Magnetization (M): Show the magnetization vector, which indicates the direction
and degree of alignment of magnetic media with an external field. In
permanent magnets, the magnetization is constant, and points to the
magnet's north pole. In ferromagnets, the magnetization is proportional
to the external field and in the same direction; in diamagnets, it is
proportional but in the opposite direction. Everywhere else it is zero.
- Show Material Type: Since all materials show up as gray, you
need this option to tell them apart:
- Diamagnets: red (
)
- Ferromagnets: green (
)
(lighter shades indicate higher permeability)
- Permanent Magnets: purple (
)
- Dielectrics: orange (
)
(lighter shades indicate stronger dielectrics)
- Resonant: light orange (
)
- Perfect Conductors: white (
)
- Imperfect Conductors: cyan (
)
(lighter shades indicate better conductors)
- Wires with Current: blue (
) or
yellow ( )
- Show Vec. Potential: Show the vector potential (A) as green (positive, toward
you) or red (negative, away from you). The vector potential is always
perpendicular to the screen.
- Show Poynting Vector: Show the Poynting vector, which indicates the direction of
energy transfer. For waves, it is in the direction of wave motion.
- Show Energy Density: Show the energy density as shades of yellow.
- Show Poynting/Energy: Show both the energy density and the
Poynting vector.
- Show Force: Show magnetic force. The total force on each
object is added up by summing over each grid square (ignoring
speed-of-light delay) and the total is shown on every grid square taken
up by the object.
- Show Effective Current: Show the effective current density in
magnetic media caused by the alignment of magnetic dipoles. This is
equal to the curl of the magnetization. So for example, for permanent
magnets, this will show you the current distribution which will generate
the same field as the permanent magnet; a square permanent magnet acts
the same as a solenoid.
- Show Magnetic Charge: Show the effective magnetic charge
density for any permanent magnets. For setups involving just permanent
magnets, we can think of the magnetic field as originating from magnetic
charges at the north and south poles of the magnets. Using those
magnetic charges, we can calculate a scalar potential for every point on
the screen (just like the electrostatic potential) and calculate the
magnetic intensity vector (H) from that potential. So if you look
the magnetic charge of a permanent magnet you see that the two poles are
oppositely charged; if you look at the H it looks like the
electric field of two parallel plates with opposite charges on each
plate (with the plates located at the poles).
- Show Curl E: Show the curl of the electric field, which is
equal to the change in magnetic field (in the absence of currents), by
one of Maxwell's equations.
- Show Bx: Show the x component of the magnetic field; green
indicates positive (to the right) and red indicates negative (to the
left).
- Show By: Show the y component of the magnetic field; green
indicates positive (up) and red indicates negative (down).
- Show Hx,Hy: Show the x or y component of the magnetic
intensity vector.
The Clear Fields button magically clears out any fields but does
not remove any currents, sources, or materials. The Clear All
button clears out everything.
The Stopped checkbox stops the applet, in case you want to take
a closer look at something, or if you want to work on something with the
mouse without worrying about it changing out from under you.
The Simulation Speed slider controls how far the waves move
between frames. If you slide this to the left, the applet will go faster
but the motion will be choppier.
The Resolution slider allows you to speed up or slow down the
applet by adjusting the resolution; a higher resolution is slower but
looks better.
The Brightness slider controls the brightness, just like on a TV
set. This can be used to view faint waves more easily.
|
 Directions_files/blank.gif) |
|