The term ''Dexel'' has two common uses:
Dexel ("depth
pixel
In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a raster image, or the smallest point in an all points addressable display device.
In most digital display devices, pixels are the ...
") is a concept used for a discretized representation of functions defined on surfaces used in geometrical modeling and physical simulation, sometimes also referred to as multilevel Z-map. Dexel is a nodal value of a
scalar or
vector field on a meshed surface. Dexels are used in
simulation
A simulation is the imitation of the operation of a real-world process or system over time. Simulations require the use of Conceptual model, models; the model represents the key characteristics or behaviors of the selected system or proc ...
of
manufacturing
Manufacturing is the creation or production of goods with the help of equipment, labor, machines, tools, and chemical or biological processing or formulation. It is the essence of secondary sector of the economy. The term may refer to ...
processes (such as
turning
Turning is a machining process in which a cutting tool, typically a non-rotary tool bit, describes a helix toolpath by moving more or less linearly while the workpiece rotates.
Usually the term "turning" is reserved for the generation ...
,
milling or
rapid prototyping
Rapid prototyping is a group of techniques used to quickly fabricate a scale model of a physical part or assembly using three-dimensional computer aided design (CAD) data.
Construction of the part or assembly is usually done using 3D printing ...
), when workpiece surfaces are subject to modifications. It is practical to express the surface evolution by dexels especially when the surface evolution scale is very different from the structural
finite element
The finite element method (FEM) is a popular method for numerically solving differential equations arising in engineering and mathematical modeling. Typical problem areas of interest include the traditional fields of structural analysis, heat t ...
3D model discretization step (e.g. in machining the depth of cut variation is often several orders of magnitude smaller (1–10 µm) than the FE model mesh step (1 mm)).
Dexel ("detector element") is the analog of a
pixel
In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a raster image, or the smallest point in an all points addressable display device.
In most digital display devices, pixels are the ...
("picture element") but native to a detector rather than a visible picture.
That is, it describes the elements in a detector, which may be processed, combined, resampled, or otherwise mangled, before creating a picture. As such, there may not be a one-to-one correspondence between the pixels in an image, and the dexels used to create that image. For example, cameras labeled as "10-megapixel" can be used to create a 640x480 picture. Using dexel terminology, the camera actually uses 10 million dexels to create a picture with 640x480 pixels.
References
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Mechanical engineering
Computer-aided manufacturing
Simulation