Page 217 - Electrical Engineering Dictionary

digitization a process applied to a con- Dill parameters three parameters, named
tinuous quantity that samples the quantity A, B, and C, that are used in the Dill exposure
first, say, in time or spatial domain, and then model for photoresists. A and B represent
quantizes the sampled value. For instance, a the bleachable and nonbleachable absorption
continuous-time signal can be first sampled coefficients of the resist, respectively, and C
and then quantized to form a digital signal, represents the first-order kinetic rate constant
which has been discretized in both time and of the exposure reaction. (Named for Freder-
magnitude. ick Dill, the first to publish this model.) Also
called the ABC parameters.
digitize the action of converting informa-
tion from analog to digital form. dilution transformer one of several
hedges, (e.g., somewhat, quite, rather, and
digitizer See data tablet. sort of) that dilute the characteristics of a
fuzzy set.
dilation a fundamental operation in math-
ematical morphology. Given a structuring
diminished radix complement form of
element B, the dilation by B is the opera-
the complement representation of negative
tor transforming X into the Minkowski sum
numbers. In the binary system, the radix
X ⊕ B, which is defined as follows:
complement is called the 2s complement and
1. If both X and B are subsets of a space E,
the diminished radix complement is called
the 1s complement.
X ⊕ B = {x + b | x ∈ X, b ∈ B}
diode a two-terminal device that permits
2. If X is a gray-level image on a space E and
the flow of electric current in only one direc-
B is a subset of E, for every p ∈ E we have
tion.
(X ⊕ B)(p) = sup X(p − b) Diodes are most often constructed by
b∈B abutting n-type and p-type regions of a semi-
conductor, that has significantly higher elec-
3. If both X and B are gray-level images on
trical conductivity in one direction (forward-
a space E, for every p ∈ E we have
biased) than the other (reverse-biased).
(X ⊕ B)(p) = sup [X(p − h) + B(h)] Diode devices may be specially designed
h∈E for low-power, high switching speed appli-
cations (signal diodes) or higher-power ap-
with the convention ∞ − ∞=−∞ when plications (rectifier diodes).
X(p − h), B(h) =±∞. (In the two items
above, X(q) designates the gray-level of the
diode detector a device that by use of rec-
point q ∈ E in the gray-level image X.) See
tification and the use of inherent nonlinearity
erosion, structuring element.
separates a modulating signal from its carrier.
dilation equation the equation
diode gun Plumbicon a Plumbicon tube
inf ty with an electron gun that operates with posi-
X
π(t) = a(n)π(2t − n) tive voltage applied to G 1 with respect to the
cathode. The diode gun principle provides a
n=−inf ty
finer beam spot size and lower beam temper-
with π(t) being scaling function and a(n) be- ature. This results in higher resolution and
ing the coefficients. It states the fact that, in improved lag performance compared to tri-
multiresolution analysis, a scaling space is ode gun tubes. The diode gun also provides
contained in a scaling space with finer scale. a much higher current reserve for highlight

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