Matches in DBpedia 2014 for { <http://dbpedia.org/resource/Petrographic_microscope> ?p ?o. }
Showing items 1 to 48 of
48
with 100 items per page.
- Petrographic_microscope abstract "A petrographic microscope is a type of optical microscope used in petrology and optical mineralogy to identify rocks and minerals in thin sections. The microscope is used in optical mineralogy and petrography, a branch of petrology which focuses on detailed descriptions of rocks. The method is called "polarized light microscopy" (PLM).Depending on the grade of observation required, petrological microscopes are derived from conventional brightfield microscopes of similar basic capabilities by: adding a polarizer filter to the light path beneath the sample slide replacing the normal stage with a circular rotating stage (typically graduated with vernier scales for reading orientations to better than 1 degree of arc) adding a second rotatable and removable polarizer filter, called the analyzer, to the light path between objective and eyepiece adding a Phase telescope, also known as a Betrand Lens, which allows the viewer to see conoscopic interference patterns adding a slot for insertion of wave platesPetrographic microscopes are constructed with optical parts that do not add unwanted polarizing effects due to strained glass, or polarization by reflection in prisms and mirrors. These special parts add to the cost and complexity of the microscope. However, a "simple polarizing" microscope is easily made by adding inexpensive polarizing filters to a standard biological microscope, often with one in a filter holder beneath the condenser, and a second inserted beneath the head or eyepiece. These might be sufficient for many non-quantitative purposes. The two filters of the petrographic microscope have their polarizing planes oriented perpendicular to one another. When only an isotropic material such as air, water, or glass exists between the filters, all light is blocked. However, most crystalline materials and minerals change the polarizing light directions, which allows some of the altered light to pass through the analyzer to the viewer. Using one polarizer allows for looking at the slide in plane polarized light, while using two allows for analysis under cross polarized light. A particular light pattern on the upper lens surface of the objectives is created as a conoscopic interference pattern characteristic of uniaxial and biaxial minerals, and produced with convergent polarized light. To observe the interference figure, true petrographic microscopes usually include an accessory called a Bertrand lens, which focuses and enlarges the figure. It is also possible to remove an eyepiece lens to make a direct observation of the objective lens surface. In addition to modifications of the microscope's optical system, petrographic microscopes allow for the insertion of specially-cut oriented filters of biaxial minerals (named the Quartz Wedge, quarter-wave mica plate and half-wave mica plate), into the optical train between the polarizers to identify positive and negative birefringence, and in extreme cases, the mineral order when needed.".
- Petrographic_microscope thumbnail LvMS-Lvm.jpg?width=300.
- Petrographic_microscope wikiPageExternalLink index.htm.
- Petrographic_microscope wikiPageExternalLink crystal.html.
- Petrographic_microscope wikiPageExternalLink polarizedintro.html.
- Petrographic_microscope wikiPageExternalLink quartzwedgefigure2.jpg.
- Petrographic_microscope wikiPageExternalLink polarizedhome.html.
- Petrographic_microscope wikiPageID "9376665".
- Petrographic_microscope wikiPageRevisionID "603752332".
- Petrographic_microscope hasPhotoCollection Petrographic_microscope.
- Petrographic_microscope subject Category:Microscopes.
- Petrographic_microscope subject Category:Optical_mineralogy.
- Petrographic_microscope type Artifact100021939.
- Petrographic_microscope type Device103183080.
- Petrographic_microscope type Instrument103574816.
- Petrographic_microscope type Instrumentality103575240.
- Petrographic_microscope type Magnifier103709206.
- Petrographic_microscope type Microscope103760671.
- Petrographic_microscope type Microscopes.
- Petrographic_microscope type Object100002684.
- Petrographic_microscope type PhysicalEntity100001930.
- Petrographic_microscope type ScientificInstrument104147495.
- Petrographic_microscope type Whole100003553.
- Petrographic_microscope comment "A petrographic microscope is a type of optical microscope used in petrology and optical mineralogy to identify rocks and minerals in thin sections. The microscope is used in optical mineralogy and petrography, a branch of petrology which focuses on detailed descriptions of rocks.".
- Petrographic_microscope label "Microscopie en lumière polarisée".
- Petrographic_microscope label "Microscopio de luz polarizada".
- Petrographic_microscope label "Microscopio polarizzatore".
- Petrographic_microscope label "Microscópio petrográfico".
- Petrographic_microscope label "Mikroskop polaryzacyjny".
- Petrographic_microscope label "Petrographic microscope".
- Petrographic_microscope label "Polarisatiemicroscoop".
- Petrographic_microscope label "Polarisationsmikroskop".
- Petrographic_microscope label "偏光顕微鏡".
- Petrographic_microscope sameAs Polarisationsmikroskop.
- Petrographic_microscope sameAs Microscopio_de_luz_polarizada.
- Petrographic_microscope sameAs Microscopie_en_lumière_polarisée.
- Petrographic_microscope sameAs Microscopio_polarizzatore.
- Petrographic_microscope sameAs 偏光顕微鏡.
- Petrographic_microscope sameAs Polarisatiemicroscoop.
- Petrographic_microscope sameAs Mikroskop_polaryzacyjny.
- Petrographic_microscope sameAs Microscópio_petrográfico.
- Petrographic_microscope sameAs m.0286g3l.
- Petrographic_microscope sameAs Q898919.
- Petrographic_microscope sameAs Q898919.
- Petrographic_microscope sameAs Petrographic_microscope.
- Petrographic_microscope wasDerivedFrom Petrographic_microscope?oldid=603752332.
- Petrographic_microscope depiction LvMS-Lvm.jpg.
- Petrographic_microscope isPrimaryTopicOf Petrographic_microscope.