A cloaking device is an energy screen generator used to render an object (typically, a space vehicle) invisible to the eye and to most sensor systems. This is accomplished by gravitational lensing, the creation of a distorted image of an object when it's light is focused by gravity. In the case of a cloaking device, the light is focused so that the object's index of refraction (the phase velocity of radiation in free space divided by the phase velocity of the same radiation in a specified medium) matches its surroundings, making the object transparent. Cloaking a ship requires precisely balancing the radiative emissions from the warp drive nacelles, dissipating all electromagnetic radiation, gravitational fields and other energy emissions emanating from the ship, and distorting space in such a way that electromagnetic radiation and energy emissions are directed around the ship through subspace at velocities faster than light.
Off-axis warp field controllers balance the radiative emissions from the warp drive nacelles. This is necessary because the power source must be in phase with the cloaking device. These devices are used on warp-capable ships without cloaking devices, as well as warp-capable ships with cloaking devices, because they increase the engine operating effeciency. If any one of these controllers are misaligned or in some way damaged it would produce a polarized, magnetic distortion, detectable by other ship's sensors. When a cloaked ship is traveling faster than light in warp, the fact that the ship is moving so quickly makes it difficult to pin-point the location of a ship even if one of the controllers are in some way damaged or misaligned.
The nullifier cores dissipate all electromagnetic radiation and other energy emissions produced by the ship and it's crew. This is done by remodulating the energy signiture to have the appearence of background energy, as well as reducing the apparent output. The amount of energy required by the nullifier cores to mask a certain amount of energy is not directly proportional to the amount of energy to be masked.
For increasingly larger amounts of energy to be masked, the amount of energy required by the nullifier cores to mask that energy becomes ever closer to being equal the amount of energy to be masked. Providing shielding against the entire electromagnetic spectrum is energy-costly, but necessary if a ship is within close proximity. However, if there are no ships within the immediate vicinity, then the nullifier cores are capable of dissipating electromagnetic radiation on the wavelengths that would only be detectable on long-range scanners, ignoring the wavelengths detectable on only short-range scanners. The green coloration is necessary on cloaking devices Mk 3.0 through Mk 3.2, because of problems with energetic effects occurring inside the cloak as a result of trapped spurious thermal emissions within the cloaking field. Another necessary function of the nullifier cores is to create a null area of gravity between the ship and the cloaking field. So that any gravity coming from the ship does not interfere with the cloaking field, or be detected by a gravimetric distortion mapping scanner on another ship.
Cloaking generator coils use a coherent graviton emission to distort
space so that incident electromagnetic radiation and other forms of energy
are directed around the ship through subspace at velocities faster than
light, making the appearance that the light or energy never left it's original
course. One of the main parts of a cloaking generator coil is a graviton
polarity source generator.
Graviton polarity source generators create a highly focused spatial distortion which directs the course of the energy and light. The graviton polarity sources in each generator feed into subspace field distortion amplifiers that are phase-synchronized with each other by a network of small conduits that allow field bleed for gravitational stability between the graviton polarity sources. These conduits are equipped with tetryon compositors, to prevent a build-up of tetryons in the conduits, which would decrease the operating efficiency and eventually significantly damage the subspace field distortion amplifiers. The flux energy output is directed and focused by a series of subspace field generator coils, according to the energy dispersal pattern. The energy dispersal pattern, or the energy transformational matrix, is the way in which the energy and light is directed around the ship. The actual subspace field generator coils are similar to warp field coils, but they create a multi-layered field in the space around the ship, not also within it. The propulsive, asymmetrical, peristaltic field distortion propels the energy faster than light. This compensates for the extra distance that the energy has to travel around the ship before returning to it's original course, and any redshift or blueshift caused by the Doppler effect, or a gravitational field.
A simplified schematic of a cloaking generator coil.
A - subspace field distortion amplifiers
B - graviton polarity source generators
C - subspace field generator coils
D - plasma buffer
E - plasma coils
A typical gravity generator on a Galaxy-Class starship, similar to the graviton polarity source generators in a cloaking generator coil.
The interior of a warp nacelle on a Galaxy-Class starship which is very simular to the Promethsus class starship. The warp coils are similar to the subspace field generators coils in a cloaking generator coil.
The cloaking generator coils are controlled by special purpose, or dedicated,
computers designed to perform this specific task. They are extremely fast
computers that contain a complex arrays of processors each designed to
perform a specific function. These computers must handle huge databases,
and perform complex mathematical operations in order to provide an accurate
energy dispersal pattern. Input data is provided for the computers by a network
of refractometers placed on the hull of the ship. The more refractometers
placed on the hull of the ship, the more effective the energy dispersal pattern.
The only limiting factor is the speed of the computers, which must provide a
realtime energy dispersal pattern to effectively cloak the ship. These computer
are completely seperate from the computers that perform other ship functions,
because they are limited to the specific function built into them. These
computers are only required on fine tuned cloaking devices, Mk 3.2 and
Magnetic constriction coils create a localized magnetic waveguide plane
the energy to pass through in subspace, which ensures proper alignment of the
energy when the ship is in warp. If a ship was using the magnetic constriction
coils while not in warp, an active magnetic interferometry scanner could detect
the use of the coils.
All of the parts of the cloaking generator coils are powered by plasma
These coils must all have an identical energy frequency. This is accomplished
by a plasma buffer. If there is no plasma buffer, then the cloaking generator
coils could easily be disrupted, by something like an ionic pulse.
There are many forms of energy dispersal patterns, some more energy
efficient or more anti-detection effective than others. The energy dispersal
pattern for a ship must be very carefully calculated. There are generally two
classifications of energy dispersal patterns: spherical cloaking, and
On the spherical cloaking mode the cloak is generated at a constant distance
from the center of the graviton polarity source generators. However, as the
gravitational effect is less significant, the shape of the field becomes more
elliptical, i.e., less spherical. This distance is controllable up to a point, when
the power system of the ship the can no longer support a field of that size, and
the cloak chaotically collapses, causing powerful gravitational waves. This
setting is intended for use during warp travel, whereby the cloak surrounds the
warp fields and effectively cloaks it also. The spherical cloaking mode
produces a noticeable distortion of visible light with some energy dispersal
patterns. This is because the field behaves as a lens, focusing light in places
and diffusing it in others. This is especially noticeable as the cloak engages
A spherical energy dispersal pattern.
On the wavemapped cloaking mode the cloak is generated at a constant
distance from the surface of the ship. It is possible to create an energy
dispersal pattern, on a very well tuned vessel, less than thirteen millimeters
from the hull by emitting the cloaking field from a series of conformal
transmission assemblies on the hull which are connected to the cloaking
generator coils. Constant computer monitoring is required at this level, and
cannot be performed at warp. Wavemapped cloaking cannot be instantly
engaged or disengaged, because of the complexity of the field geometry. The
cloak is carefully powered down to avoid damaging the cloaking device. In an
atmosphere, gas will get trapped inside the cloak if wavemapped. This will
cause sound vibrating between the hull and cloaking field, making an audible
Subspace listening posts, gravitic sensor nets and tachyon heterodyne
detection grids can be used to track cloaked ships.
Subspace listening posts are designed to listen for any subspace radio,
subspace field distortions (these indicate the presence of a warp drive), any
subspace compression (a possible warp drive error), or subspace shock
waves small enough to be undetectable by standard sensor arrays (these
indicate a spontaneous warp field collapse.) Subspace relay stations, which
boost subspace radio transmissions, can be converted to subspace listening
posts without much difficulty.
Gravitic sensor nets are a network of detection devices that are partially
effective in detecting cloaked ships. Gravitic sensor nets utilize highly sensitive
gravimetric distortion mapping scanners to map the gravitational forces
throughout the area in which it would be probable that a cloaked ship would
pass. If a cloaked ship's nullifier cores were not creating a complete area of
null gravity around the ship, then it would be possible to observe the changes in
the space around the ship.
Tachyon heterodyne detection grids are a network of active tachyon beams
used to detect cloaked ships passing through the net. Tachyon heterodynes
are charged tachyons having alternating currents of two different frequencies
that are combined to generate a new frequency equal to the sum or difference
of the two.
As a cloak engages and disengages, a momentary gravitational wave forms
from the graviton polarity sources, while the subspace field distortion
amplifiers phase-synchronize with each other. (Gravitational waves also called
gravitational radiation or spatial ripples.) A gravitational wave is a ripple in the
curvature of space-time In other words, it is a propagating gravitational field, or
propagating pattern of strain, traveling at the speed of light. It carries energy
and can exert forces on matter in its path, producing, for instance, very small
vibrations in elastic bodies. As the ripple forms, the ships inertial damping
system will attempt to respond. But because,on average, the intertial damping
system lags 295 milliseconds to respond, there is a slight strain of the physical
spaceframe of the craft. If the ripple is fairly limited, no considerable effect will
result, but, should the ripple be large, the systems will fail to adequately
compensate and the ripple can cause a significant effect on the ship and crew.
This distortion, although the relatively weak interaction between gravitional
radiation and matter, can create an effect similar to that of spatial interphase,
which alters the neural pathways in the brain, effectively rendering any
humanoids exposed to the spatial radiation insane, or worse. Statistically, on a
Mk 3.2a cloaking device, a ripple large enough that it cannot be adequately
compensated for, should occur some 0.00007854% (39,271/50,000,000,000)
of the time. A build-up of tetryons in the conduits that allow field bleed between
the graviton polarity sources will significantly increase the chance of a spatial
ripple occuring. A neural disturbance should occur approximately
0.0000001386% of the time, with a 0.000000000341%
(341/100,000,000,000,000 ) chance of complete structural failure due to
spatial ripple stress.
In addition to the production of gravitational waves, cloaking devices
several other significant disadvantages. The greatest disadvantage is the
tremendous amount of energy required to maintain all of the parts of the
If a ship had the ability to generate enough energy to to maintain the
device as well as defensive shields, the nullifier cores could neither mask all of
the erergy required to accomplish this, nor the interference created by
defensive shields. In addition, the spatial distortions created by defensive
shields would mean that the shield itself would have to exist within the cloaking
field, and the larger the cloaking field is, the more energy is required to
generate it. These reasons completely eliminate the possibility of using
When a starship's cloaking device is active, several ship's systems operate
under special protocols to minimize the interference of the cloaking device.
If the cloaking generator coils distorted space so that all incident
electromagnetic radiation and other forms of energy were directed around the
ship, then the sensor systems could not gather any data. As a result, the
cloaking generator coils create frequency windows to allow specific
wavelengths to pass through the cloaking field at certain times. This limits the
gathering of many types of scientific and tactical data, but is adequate for most
situations. Active scanners may not be used while the cloaking device is
Although the transporter system could be tuned to the same frequency as
cloaking device, the gravitational distortions usually prevent usage of the
Phased energy weapons make use of the rapid nadion effect. This is very
disruptive to the cloaking device's plasma coils, even with a plasma buffer, and
therefore cannot be used. If a cloaked ship did use their phasers, the beam
would be bent off course and hit the ship at a diametric point and angle. In
addition, the nullifier cores would attempt to dissipate the phaser beam and
remodulate its energy signiture to give the appearence of background
emmisions. The cloaking field would most likely collapse, causing powerful
gravitational waves. However, it is possible for a phaser to penetrate the cloak
from the outside if it is tuned to the frequency of a window opened in the cloak
for sensory input.
Warp drive operation is considerably affected by the cloaking device. The
geometry of the warp field must be significantly altered because of the spatial
distortions created by the cloaking device. Warp drive control software works
in parallel with the cloaking generator coil's dedicated computer to minimize
the effect on both systems. The translational field interaction between the
cloaking device and the warp drive is somewhat chaotic, creating potentially
catastrophic effects. Such as a spontaneous field collapse of the warp field or
subspace compression. This is why subspace listening posts are an efficient
way of tracking cloaked ships.
It is possible to open an interference window in a finely tuned cloak,
so that a
photon torpedo will pass through, as opposed to being bent off course or even
crushed by the gravitational distortion. This interference window is generated
by, at the moment of firing, a cloaking generator coil to operate on a different
frequency than the other cloaking generator coils. This is accomplished by
temporarily disconnecting the plasma coil powering the cloaking generator coil
for the area where the torpedo will leave the cloaking field from the plasma
buffer. The translational field interaction between the cloaking generator coils
causes a gap to open in the cloak. The calculations that are necessary to allow
the ship to properly cloak after the launch of the torpedo are very complex. As
a result, there is a lag in firing, the length of which depends on the speed of the
cloaking generator coil's dedicated computer.
Because the navigational deflector dish radiates significant amounts of
subspace and electromagnetic radiation, it cannot be used when cloaked
without an extremely powerful network of nullifier cores, which would consume
a considerable amount of energy. Instead of this, a variant of the transporter
system is used. This device converts the micrometeorite particulates to
energy, lets the energy be directed around the ship as with all of the other light
and energy, and then converts the energy back to matter. This method is only
used when a ship is in very close proximity. Otherwise the magnetic
constriction coils are tuned with the cloaking generator coils to reflect
interstellar gases and micrometeoroid particulates. This method is more
energy effecient than the method using a variant of the transporter system.
A navigational deflector on the USS Agamemnon.
A molecular phase inverter is a device that could alter the molecular structure
of matter so it could pass through normal matter and energy at certain angles.
The angles that phased matter can pass through normal matter and energy at
are determined by the matter's quantum state. Theoretically, if quantum
mechanical subatomic particles were phased, they could pass through normal
matter at every possible angle. In this case, there would be absolutely no
source of drag or resistance. The inertia of a body could carry it on the same
course at the same velocity as when it was phased until the body was
An interphase generator is a molecular phase inverter combined with a
cloaking device. Matter exposed to this interphase generator would partially
exist on a parallel spatial plane (similar to that of subspace) and would
therefore be undetectable to any known sensing device. This is similar to
coplanar spatial interphase, a time-space phenomenon in which two or more
dimensions overlap and connect. Matter so cloaked can pass through normal
matter, with the same limitations previously discussed. When phased matter
passes through normal matter chroniton particles are formed. A modified
anyon emitter can clear chroniton particles and when set to a sufficient
strength, dephase phased matter.
Cloaking devices have been classified into the following categories according
to their overall effectiveness:
Mk 1 Cloak: Original usage, early Warbirds only. Used electromagnetic
radiation shielding quite effectively to cloak only visible and near-visible
radiation. Can instantaneously cloak and decloak, but required large amounts
Mk 2 Cloak: A major improvement on the Mk 1, this device cloaked all
electromagnetic radiation, except high energy Gamma rays. Can
instantaneously cloak and decloak, but was remarkably inefficient. Craft:
Romulan Scouts and Warbirds, also Klingon D-7 Cruisers, and later the joint
Romulan/Klingon scout and Bird Of Prey.
Mk 3.0 Cloak: The first gravity distorting cloak. The early prototype craft
problems with energetic effects occurring inside the cloak as a result of
trapped spurious thermal emissions within the cloaking field. This was
overcome by giving the craft a green coloration. This tuned the thermal energy
to a frequency where it could leak very slowly through the cloak without
revealing the ships presence, still common practice on most cloaked vessels.
This early Mk 3 had only the spherical field setting and could not be effectively
wavemapped. It could not instantly cloak and decloak, but saw much use on
most Romulan craft and the Bird Of Prey.
Mk 3.1 Cloak: This improved device featured instantaneous propagation of
spherical cloak, and first saw use of the wavemapped cloak. It is reported to
have been used as above and as an upgraded cloak for D-7 Cruisers. A green
coloration was still necessary.
Mk 3.2 Cloak: This version saw the creation of the fine tuned cloak, using
special dedicated computers. This device was perhaps first created by the
Klingons, but required large power reserves. The Romulans later reworked the
idea into a more efficient form (officially designated the Mark 3.2a). The old
cloak is still in active service on older Klingon craft.
Mk 3.2a Cloak: Romulan reworking of the 3.2. No special coloration of the
is necessary, although the nullifier cores require less energy when the ship has
a green color. The cloak is still extensively used by Romulans and Klingons
Mk 3.3 Cloak: This latest version allowed powering down of all non-finely
cloaks instantly. It is only fitted, as far as is known, to Romulan Warbirds.
Klingons claim to still use the 3.2a.
Experimental Mk 4 Cloak: There is an experimental cloaking device which
utilizes a highly-wavemapped, adaptive, asymmetrical dispersion pattern. This
cloaking device's cloaking generator coils are equipped with field actuators
that change the dispersion pattern, to be most efficient in any interstellar
condition, considering many variables, such as gas density, electric and
magnetic fields, and fluctuations in the subspace domain. These field
actuators compensate for any of these variables or active scans if the vicinity
of the cloaked ship is being probed. There is no danger of a spatial ripple
occurring. This would render a ship undetectable, except with a tachyon
heterodyne detection grids, which, if powerful enough, could detect a ship that
was cloaked in this manner.