Optical fabrication and testing spans an enormous range of manufacturing procedures and optical test configurations.
The manufacture of a conventional spherical lens typically begins with the generation of the optic's rough shape by grinding a glass blank. This can be done, for example, with ring tools. Next, the lens surface is polished to its final form. Typically this is done by lapping—rotating and rubbing the rough lens surface against a tool with the desired surface shape, with a mixture of abrasives and fluid in between.
Typically a carved pitch tool is used to polish the surface of a lens. The mixture of abrasive is called slurry and it is typically made from cerium or zirconium oxide in water with lubricants added to facilitate pitch tool movement without sticking to the lens. The particle size in the slurry is adjusted to get the desired shape and finish.
During polishing, the lens may be tested to confirm that the desired shape is being produced, and to ensure that the final shape has the correct form to within the allowed precision. The deviation of an optical surface from the correct shape is typically expressed in fractions of a wavelength, for some convenient wavelength of light (perhaps the wavelength at which the lens is to be used, or a visible wavelength for which a source is available). Inexpensive lenses may have deviations of form as large as several wavelengths (λ, 2λ, etc.). More typical industrial lenses would have deviations no larger than a quarter wavelength (λ/4). Precision lenses for use in applications such as lasers, interferometers, and holography have surfaces with a tenth of a wavelength (λ/10) tolerance or better. In addition to surface profile, a lens must meet requirements for surface quality (scratches, pits, specks, etc.) and accuracy of dimensions.
In scientific inquiry and academic research, fabrication is the intentional misrepresentation of research results by making up data, such as that reported in a journal article. As with other forms of scientific misconduct, it is the intent to deceive that marks fabrication as highly unethical and different from scientists deceiving themselves. In some jurisdictions, fabrication may be illegal.
Examples of activities that constitute fabrication include:
Outright synthesis of experimental data; reporting experiments that were never conducted. Sometimes referred to as "drylabbing".
"Fudging", "massaging", or outright manufacture of experimental data.
Some forms of unintentional academic incompetence or malpractice can be difficult to distinguish from intentional fabrication. Examples of this include the failure to account for measurement error, or the failure to adequately control experiments for any parameters being measured.
Fabrication can also occur in the context of undergraduate or graduate studies wherein a student fabricates a laboratory or homework assignment. Such cheating, when discovered, is usually handled within the institution, and does not become a scandal within the larger academic community (as cheating by students seldom has any academic significance).
Precision is the authorized march of Royal Military College of Canada. The RMC band performs Precision on parades for march pasts, on Ex Cadet Weekends for the parade to the Memorial Arch, and on the return, the Cadet Wing sings Tom Gelley’s words to welcome the Ex Cadets to the Parade Square.
Precision was composed in 1932 by Denise Chabot, wife of Major C. A. Chabot, a Royal Canadian Artillery officer on staff as professor of French at the College at the time. She earned the degree of Associate of the Royal Conservatory of Music and was the president of the Kingston Music Club.
Precision was inspired by "Madelon", one of the popular marching songs sung and whistled by the cadets marching on their way to the Riding School, and the favourite song of the Class of 1932. Mme Chabot improvised a variation on the song, to represent the cadence of the cadets on the march. The composition starts, “We are the gentlemen cadets of RMC We have sworn to love and serve Her Majesty…”
In statistics, the dual term variability is preferred to the use of precision. Variability is the amount of imprecision.
There can be differences in usage of the term for particular statistical models but, in common statistical usage, the precision is defined to be the reciprocal of the variance, while the precision matrix is the matrix inverse of the covariance matrix.
One particular use of the precision matrix is in the context of Bayesian analysis of the multivariate normal distribution: for example, Bernardo & Smith prefer to parameterise the multivariate normal distribution in terms of the precision matrix rather than the covariance matrix because of certain simplifications that then arise.
The term precision in this sense (“mensura praecisionis observationum”) first appeared in the works of Gauss (1809) “Theoria motus corporum coelestium in sectionibus conicis solem ambientium” (page 212). Gauss’s definition differs from the modern one by a factor of . He writes, for the density function of a normal random variable with precision h,
“What we have developed is a technique to easily fabricate defect-free, strong membranes that have rigid nanopores that can be precisely controlled to allow different-sized molecules to pass through,” adds Yu, a core faculty member at the UB RENEW Institute.
SMITH TWP. − Trailstar International, a MACTrailer Enterprises company, is undergoing a $10 million expansion project ... "Our main concern is not more trailers," he said. "Our main concern is keeping the production where the levels are at today and making sure that our product is built with precise engineering and fabrication." ... On Twitter. @kbyerREP
SOUTH SAN FRANCISCO, Calif. & SAN RAFAEL, Calif ...Twist Bioscience Corporation (NASDAQ... This precise and rational approach to library fabrication combined with sophisticated bioinformatics and software expertise expedites antibody discovery by decreasing risk, increasing speed, and lowering the failure rate for antibody therapeutic development ... PUB.
Using a commercial femtosecond laser, the scientists etch out special grooves in the glass that allow for the precise placement of the essential components of their laser. Even at micron level precision fabrication, the grooves and the components are not sufficiently precise by themselves to reach laser quality alignment ...Applications and beyond ... DOI.
About you.Degree in engineering, manufacturing, or equivalent proven experience in a similar sales estimating role within the precision engineering sector.Strong understanding of machining, fabrication, welding, pressing, painting, and laser cutting processes.Excellent analytical ...
The principle behind liquid cooling your PC parts is pretty simple. cool liquid comes in, pulls heat from the component, warm liquid moves out, fans cool it down and expel hot air outside the PC case... Dr ... 3D metal printing is used to fabricate this ideal shape with much more precision than is possible or economical with conventional tools ... Desktop PCs.
"After the design was complete, we ordered the customized fabrics, which are specially made from mulberry silk. Then, our skilled artisans drew the patterns by hand, followed by precise structural tailoring and hand sewing." ... It is worth noting that the silk fabric used will not ...
Jumpers arrived with large, military patches on the shoulders and elbows, and worn with short shorts ... Read More ... “Each piece will come out slightly differently, and gives the clothes a flavour you don’t get in clothes where the fabric is dyed first.”. For a house known for its elegant precision, this is something of a departure ... That is key ... Weekender.
Jumpers also arrived with large, military patches on the shoulders and elbows, and worn with short shorts ... Read More ... "Each piece will come out slightly differently, and gives the clothes a flavour that you don’t get in clothes where the fabric is dyed first.". For a house known for its elegant precision, this is of course something of a departure.
Trade missions this week have taken New Mexico. Gov ... Both women spoke at a business conference in Taipei joining U.S. and Taiwan leaders ... border with Mexico ... Construction started in 2021 on that sprawling facility that will utilize precision trademark technology for semiconductor fabrication with the capacity to produce 20,000 wafers per month ... .
Using a direct-write scanning tunneling microscopy (STM) based process, the nanometer-scale metal contacts were fabricated on individual GNRs and could control the electronic character of the GNRs ... Semiconductor properties can be induced in graphene by making it very small or by fabricating it into specific shapes—like ribbons.
UNITED NATIONS (AP) — Many leaders saying many things about many topics that matter to them, to their regions, to the world. That’s what the U.N ... disinformation. It is an era of snack news, attention economy, the fabrication of facts, and of increasing disagreements about facts precisely because we no longer trust any narratives ...All rights reserved.