#lens

• Anastigmat — A complex optical system or photographic lens, composed of an assembly of multiple lenses with different refractive indices, mathematically calculated to simultaneously correct astigmatism, field curvature, and chromatic aberration. This type of high-precision lens allows perfect and uniform focusing of light rays across the entire surface of the focal plane, ensuring extremely sharp and undistorted images both at the center and the edges.
• Anastigmatic — Free from astigmatism; optimally corrected from a geometric and optical standpoint to eliminate asymmetric convergence aberrations of oblique light rays. It is applied to systems, lenses, aspherical surfaces, or light beams capable of forming a perfect point-like image of a point object, offering exceptional flatness of the visual field.
• Anastigmatism — An ideal optical property or characteristic of a lens or mirror system being completely free from astigmatism; the absence of asymmetric focusing distortions, allowing oblique light rays passing through the system to converge into a single precise focal point. This structural phenomenon guarantees uniform sharpness and an exceptional flatness of the image across the entire surface of the projection plane, eliminating marginal blurring.
• Andrusovo — A rural locality situated in the Smolensk Oblast, Russian Federation, globally famous in historiography due to the 'Truce of Andrusovo' (1667). This structural historical treaty, signed between the Tsardom of Russia and the Polish-Lithuanian Commonwealth, ended the Thirteen Years' War and geopolitically reshaped Eastern Europe.
• Baikal anemone — A species of perennial herbaceous plant in the family Ranunculaceae, native to the temperate regions of Eastern Asia, particularly around Lake Baikal in Siberia, as well as Mongolia and northern China. This forest plant develops a slender, creeping rhizome, delicate stems covered with fine hairs, and solitary flowers of an immaculate white, being a specific floristic element of Asian mountain and subalpine forest ecosystems.
• Antihalation — Serving to prevent, reduce, or eliminate the formation of a parasitic halo around highly illuminated points on a photographic or radiographic image. In a technical sense, it refers to special films or light-absorbing layers applied to the film base to prevent the internal reflection of rays back through the emulsion.
• Anti-reflective — Reducing, eliminating, or preventing unwanted light reflections on a transparent surface. The term describes thin protective coatings (anti-reflective treatment) applied to eyeglass lenses, camera objectives, monitor screens, or windows to enhance useful light transmission, improve contrast, and reduce eye strain.
• Antigypsyist — The feminine form of the adjective or noun antițigănist; relating to the assembly of manifestations, archaic laws, mentalities, or actions based on ethnic intolerance (e.g., antigypsyist propaganda, antigypsyist mentality) or a female who discriminates against people of Romani origin.
• Antitrinitarian — The feminine form of the term antitrinitar; it characterizes a doctrine, a church, a religious movement, or a community that rejects the dogma of the Holy Trinity. It also designates a female adherent to Unitarian or Arian theological principles, advocating for the absolute oneness of the deity and denying the co-essentiality of Jesus Christ with God the Father.
• Anti-unionist — The feminine form of the term antiunionist; it characterizes a movement, a faction, a gazette, or a political stance opposing state or labor union fusion and integration (e.g., the anti-unionist camp in Moldavia in 1859). As a noun, it designates a female who actively or theoretically campaigns against a political, territorial, or economic union.
• Anti-vaxxer — The feminine form of the term antivaccinist; a female who opposes vaccination, rejecting the administration of sera for ideological, religious, or political reasons. As an adjective, it characterizes a movement, a campaign, a rhetoric, or a social stance directed against mass immunization and public health policies promoted by the scientific community.
• Apium — A genus of herbaceous plants within the family Apiaceae (Umbelliferae), distributed worldwide, whose most widely cultivated and known species for its aromatic and nutritional qualities is Apium graveolens (common celery, including the root, leaf, and stalk/apio varieties).
• Aplanatic — Pertaining to or relating to aplanatism; an optical system (objective, lens, or mirror) that is rigorously corrected for both spherical aberration and coma aberration (Abbe's sine condition). This high-precision system allows the formation of a perfectly sharp and point-like image for an object located on the main optical axis, eliminating asymmetrical distortions of light beams.
• Aplanatism — The property or geometric condition of an optical system to simultaneously correct and eliminate both spherical aberration and coma aberration for a given point-like object. This physical phenomenon is achieved through strict compliance with Abbe's sine condition, ensuring the formation of exceptionally sharp and perfectly stigmatic images in the vicinity of the main optical axis.
• Apochromat — A complex optical system consisting of multiple lenses made from different types of glass, capable of correcting chromatic aberration for three distinct wavelengths of the visible spectrum and spherical aberration for two wavelengths. This high-precision device ensures an identical focal point for red, green, and blue colors, completely eliminating parasitic color fringes from the edges of captured images.
• Apochromatic — Pertaining to an apochromat, relating to optical systems capable of simultaneously correcting chromatic aberrations for three primary colors; characterized by the absence of the secondary spectrum and delivering an image of extreme color fidelity. It applies to professional photographic lenses, high-end binoculars, and microscopes designed for advanced research.
• Aristotelia chilensis — A species of exotic evergreen shrub in the Elaeocarpaceae family, native to the temperate rainforests of Chile and Argentina, popularly known as maqui or maqui berry. The plant produces small, globose, dark purple to black berries, which are extensively studied and globally valued for their exceptionally high concentration of antioxidants (anthocyanins and polyphenols), possessing remarkable anti-inflammatory and therapeutic properties.
• Aspheric — Not spherical; a geometric surface or optical component (lens, prism, mirror) whose profile deviates in a calculated manner from the shape of a perfect sphere. In optical engineering, aspherical surfaces are structurally designed to eliminate marginal spherical aberrations, allowing precise focusing of light rays into a single focal point and delivering superior image clarity with fewer lenses.
• Astigmatic — The feminine form of the word 'astigmat'; a woman or female person suffering from astigmatism; as an adjective, it refers to a manifestation, an ocular anatomical structure, a lens, or an image affected by this refractive error or designed to treat it.
• Astigmatic — The feminine form of the word 'astigmatic'; it refers to a woman affected by astigmatism or to a manifestation, lens, or ocular structure displaying characteristics specific to this optical focusing aberration or used for its correction.