IPC Publication
G
PHYSICS

Note(s)

  • In this section, the following term is used with the meaning indicated:
    • "variable" (as a noun) means a feature or property (e.g., a dimension, a physical condition such as temperature, a quality such as density or colour) which, in respect of a particular entity (e.g., an object, a quantity of a substance, a beam of light) and at a particular instant, is capable of being measured; the variable may change, so that its numerical expression may assume different values at different times, in different conditions or in individual cases, but may be constant in respect of a particular entity in certain conditions or for practical purposes (e.g., the length of a bar may be regarded as constant for many purposes).
  • Attention is drawn to the definitions of terms or expressions used. Some appear in the notes of several of the classes in this section, see in particular the definition of "measuring" in class G01. Others appear in paragaph 187 of the Guide to the IPC, see in particular the definitions of "control" and "regulation".
  • Classification in this section may present more difficulty than in other sections, because the distinction between different fields of use rests to a considerable extent on differences in the intention of the user rather than on any constructional differences or differences in the manner of use, and because the subjects dealt with are often in effect systems or combinations, which have features or parts in common, rather than "things", which are readily distinguishable as a whole. For example, information (e.g., a set of figures) may be displayed for the purpose of education or advertising ( G09), for enabling the result of a measurement to be known ( G01), for signalling the information to a distant point or for giving information which has been signalled from a distant point ( G08). The words used to describe the purpose depend on features that may be irrelevant to the form of the apparatus concerned, for example, such features as the desired effect on the person who sees the display, or whether the display is controlled from a remote point. Again, a device which responds to some change in a condition, e.g., in the pressure of a fluid, may be used, without modification of the device itself, to give information about the pressure ( G01L) or about some other condition linked to the pressure (another subclass of class G01, e.g., G01K for temperature), to make a record of the pressure or of its occurrence ( G07C), to give an alarm ( G08B), or to control another apparatus ( G05).
    • The classification scheme is intended to enable things of a similar nature (as indicated above) to be classified together. It is therefore particularly necessary for the real nature of any technical subject to be decided before it can be properly classified.
INSTRUMENTS
G01
MEASURING; TESTING

Note(s) [7]

  • This class covers, in addition to "true" measuring instruments, other indicating or recording devices of analogous construction, and also signalling or control devices insofar as they are concerned with measurement (as defined in Note 2 below) and are not specially adapted to the particular purpose of signalling or control.
  • In this class, the following term is used with the meaning indicated:
    • "measuring" is used to cover considerably more than its primary or basic meaning. In this primary sense, it means finding a numerical expression of the value of a variable in relation to a unit or datum or to another variable of the same nature, e.g. expressing a length in terms of another length as in measuring a length with a scale; the value may be obtained directly (as just suggested) or by measuring some other variable of which the value can be related to the value of the required variable, as in measuring a change in temperature by measuring a resultant change in the length of a column of mercury. However, since the same device or instrument may, instead of giving an immediate indication, be used to produce a record or to initiate a signal to produce an indication or control effect, or may be used in combination with other devices or instruments to give a conjoint result from measurement of two or more variables of the same or different kinds, it is necessary to interpret "measuring" as including also any operation that would make it possible to obtain such a numerical expression by the additional use of some way of converting a value into figures. Thus the expression in figures may be actually made by a digital presentation or by reading a scale, or an indication of it may be given without the use of figures, e.g. by some perceptible feature (variable) of the entity (e.g. object, substance, beam of light) of which the variable being measured is a property or condition or by an analogue of such a feature (e.g. the corresponding position of a member without any scale, a corresponding voltage generated in some way). In many cases there is no such value indication but only an indication of difference or equality in relation to a standard or datum (of which the value may or may not be known in figures); the standard or datum may be the value of another variable of the same nature but of a different entity (e.g. a standard measure) or of the same entity at a different time.
      • In its simplest form, measurement may give merely an indication of presence or absence of a certain condition or quality, e.g. movement (in any direction or in a particular direction), or whether a variable exceeds a predetermined value.
  • Attention is drawn to the Notes following the titles of class B81 and subclass B81B relating to "microstructural devices" and "microstructural systems" and the Notes following the title of subclass B82B relating to "nanostructures".
  • Attention is drawn to the Notes following the title of section G, especially as regards the definition of the term "variable".
  • In many measuring arrangements, a first variable to be measured is transformed into a second, or further, variables. The second, or further, variables may be (a) a condition related to the first variable and produced in a member, or (b) a displacement of a member. Further transformation may be needed.
    • When classifying such an arrangement, (i) the transformation step, or each transformation step, that is of interest is classified, or (ii) if interest lies only in the system as a whole, the first variable is classified in the appropriate place.
    • This is particularly important where two or more conversions take place, for instance where a first variable, for example pressure, is transformed into a second variable, for example an optical property of a sensing body, and that second variable is expressed by means of a third variable, for example an electric effect. In such a case, the following classification places should be considered: the place for the transformation of the first variable, that for sensing the condition caused by that variable, subclass G01D for expression of the measurement, and finally the place for the overall system, if any.
  • The measurement of change in the value of a physical property is classified in the same subclass as the measurement of that physical property, e.g. measurement of expansion of length is classified in subclass G01B.
DG01N
INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q)

Note(s) [5]

  • In this subclass, the following terms are used with the meanings indicated:
    • "investigating" means testing or determining;
    • "materials" includes solid, liquid or gaseous media, e.g. the atmosphere.
  • Attention is drawn to the Notes following the title of class G01.
  • Investigating the properties of materials, specially adapted for use in processes covered by subclass B23K, is classified in group B23K 31/12.
DG01N 21/00
Investigating or analysing materials by the use of optical means, i.e. using infra-red, visible or ultra-violet light (G01N 3/00-G01N 19/00 take precedence) [2006.01]

Note(s) [7]

  • This group does not cover the investigation of spectral properties of light per se, or measurements of the properties of materials where spectral properties of light are sensed and primary emphasis is placed on creating, detecting or analysing the spectrum providing that the properties of the materials to be investigated are of minor importance. Those subjects are covered by group G01J 3/00.
G01N 21/01
•
Arrangements or apparatus for facilitating the optical investigation [2006.01]
G01N 21/03
•
•
Cuvette constructions [2006.01]
G01N 21/09
•
•
•
adapted to resist hostile environments or corrosive or abrasive materials [2006.01]
G01N 21/11
•
•
Filling or emptying of cuvettes [2006.01]
G01N 21/13
•
•
Moving of cuvettes or solid samples to or from the investigating station [2006.01]
G01N 21/15
•
•
Preventing contamination of the components of the optical system or obstruction of the light path [2006.01]
G01N 21/17
•
Systems in which incident light is modified in accordance with the properties of the material investigated (where the material investigated is optically excited causing a change in wavelength of the incident light G01N 21/63) [2006.01]
G01N 21/19
•
•
Dichroism [2006.01]
G01N 21/21
•
•
Polarisation-affecting properties (G01N 21/19 takes precedence) [2006.01]
G01N 21/23
•
•
•
Bi-refringence [2006.01]
G01N 21/25
•
•
Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands [2006.01]
G01N 21/27
•
•
•
using photo-electric detection (G01N 21/31 takes precedence) [2006.01]
G01N 21/29
•
•
•
using visual detection (G01N 21/31 takes precedence) [2006.01]
G01N 21/31
•
•
•
Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry [2006.01]
G01N 21/33
•
•
•
•
using ultra-violet light (G01N 21/39 takes precedence) [2006.01]
G01N 21/35
•
•
•
•
using infra-red light (G01N 21/39 takes precedence) [2014.01]
G01N 21/3504
•
•
•
•
•
for analysing gases, e.g. multi-gas analysis [2014.01]
G01N 21/3518
•
•
•
•
•
•
Devices using gas filter correlation techniques; Devices using gas pressure modulation techniques [2014.01]
•
•
•
•
•
•

Note(s) [2014.01]

  • This group also covers devices without instrumental sources, e.g. radiometric-type devices using ambient infra-red light.
G01N 21/3554
•
•
•
•
•
for determining moisture content [2014.01]
G01N 21/3559
•
•
•
•
•
•
in sheets, e.g. in paper [2014.01]
G01N 21/3563
•
•
•
•
•
for analysing solids; Preparation of samples therefor [2014.01]
G01N 21/3577
•
•
•
•
•
for analysing liquids, e.g. polluted water [2014.01]
G01N 21/3581
•
•
•
•
•
using far infra-red light; using Terahertz radiation [2014.01]
G01N 21/3586
•
•
•
•
•
•
by Terahertz time domain spectroscopy [THz-TDS] [2014.01]
G01N 21/359
•
•
•
•
•
using near infra-red light [2014.01]
G01N 21/37
•
•
•
•
•
using pneumatic detection [2006.01]
G01N 21/39
•
•
•
•
using tunable lasers [2006.01]
G01N 21/41
•
•
Refractivity; Phase-affecting properties, e.g. optical path length (G01N 21/21 takes precedence) [2006.01]
G01N 21/43
•
•
•
by measuring critical angle [2006.01]
G01N 21/45
•
•
•
using interferometric methods; using Schlieren methods [2006.01]
G01N 21/47
•
•
Scattering, i.e. diffuse reflection (G01N 21/25, G01N 21/41 take precedence) [2006.01]
G01N 21/49
•
•
•
within a body or fluid [2006.01]
G01N 21/55
•
•
Specular reflectivity [2014.01]
G01N 21/552
•
•
•
Attenuated total reflection [2014.01]
G01N 21/57
•
•
•
Measuring gloss [2006.01]
G01N 21/59
•
•
Transmissivity (G01N 21/25 takes precedence) [2006.01]
G01N 21/61
•
•
•
Non-dispersive gas analysers [2006.01]
G01N 21/62
•
Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light [2006.01]
G01N 21/63
•
•
optically excited [2006.01]
G01N 21/64
•
•
•
Fluorescence; Phosphorescence [2006.01]
G01N 21/65
•
•
•
Raman scattering [2006.01]
G01N 21/66
•
•
electrically excited, e.g. electroluminescence [2006.01]
G01N 21/68
•
•
•
using high frequency electric fields [2006.01]
G01N 21/69
•
•
•
specially adapted for fluids [2006.01]
G01N 21/70
•
•
mechanically excited, e.g. triboluminescence [2006.01]
G01N 21/71
•
•
thermally excited [2006.01]
G01N 21/72
•
•
•
using flame burners [2006.01]
G01N 21/73
•
•
•
using plasma burners or torches [2006.01]
G01N 21/74
•
•
•
using flameless atomising, e.g. graphite furnaces [2006.01]
G01N 21/75
•
Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated (systems in which material is burnt in a flame or plasma G01N 21/72, G01N 21/73) [2006.01]
G01N 21/76
•
•
Chemiluminescence; Bioluminescence [2006.01]
G01N 21/77
•
•
by observing the effect on a chemical indicator [2006.01]
G01N 21/78
•
•
•
producing a change of colour [2006.01]
G01N 21/79
•
•
•
•
Photometric titration [2006.01]
G01N 21/80
•
•
•
•
Indicating pH value [2006.01]
G01N 21/81
•
•
•
•
Indicating humidity [2006.01]
G01N 21/82
•
•
•
producing a precipitate or turbidity [2006.01]
G01N 21/83
•
•
•
•
Turbidimetric titration [2006.01]
DG01N 21/84
•
Systems specially adapted for particular applications [2006.01]
G01N 21/85
•
•
Investigating moving fluids or granular solids [2006.01]
G01N 21/86
•
•
Investigating moving sheets (G01N 21/89 takes precedence) [2006.01]
G01N 21/87
•
•
Investigating jewels (G01N 21/88 takes precedence) [2006.01]
G01N 21/88
•
•
Investigating the presence of flaws, defects or contamination [2006.01]
G01N 21/89
•
•
•
in moving material, e.g. paper, textiles (G01N 21/90, G01N 21/91, G01N 21/94 take precedence) [2006.01]
G01N 21/892
•
•
•
•
characterised by the flaw, defect or object feature examined [2006.01]
G01N 21/894
•
•
•
•
•
Pinholes [2006.01]
G01N 21/896
•
•
•
•
•
Optical defects in or on transparent materials, e.g. distortion, surface flaws [2006.01]
G01N 21/898
•
•
•
•
•
Irregularities in textured or patterned surfaces, e.g. textiles, wood [2006.01]
G01N 21/91
•
•
•
using penetration of dyes, e.g. fluorescent ink [2006.01]
G01N 21/93
•
•
•
Detection standards; Calibrating [2006.01]
G01N 21/94
•
•
•
Investigating contamination, e.g. dust (G01N 21/85 takes precedence) [2006.01]
G01N 21/95
•
•
•
characterised by the material or shape of the object to be examined (G01N 21/89-G01N 21/91, G01N 21/94 take precedence) [2006.01]
G01N 21/952
•
•
•
•
Inspecting the exterior surface of cylindrical bodies or wires (G01N 21/956 takes precedence) [2006.01]
G01N 21/954
•
•
•
•
Inspecting the inner surface of hollow bodies, e.g. bores [2006.01]
G01N 21/958
•
•
•
•
Inspecting transparent materials [2006.01]
DG01N 22/00
Investigating or analysing materials by the use of microwaves (G01N 3/00-G01N 17/00, G01N 24/00 take precedence) [2006.01]
G01N 22/02
•
Investigating the presence of flaws [2006.01]
G01N 22/04
•
Investigating moisture content [2006.01]
DG01N 23/00
Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N 3/00-G01N 17/00, G01N 21/00 or G01N 22/00 [2006.01]
G01N 23/02
•
by transmitting the radiation through the material [2006.01]
DG01N 23/04
•
•
and forming images of the material [2018.01]
G01N 23/041
•
•
•
Phase-contrast imaging, e.g. using grating interferometers [2018.01]
G01N 23/044
•
•
•
using laminography or tomosynthesis [2018.01]
G01N 23/046
•
•
•
using tomography, e.g. computed tomography [CT] [2018.01]
G01N 23/05
•
•
•
using neutrons [2006.01]
G01N 23/06
•
•
and measuring the absorption [2018.01]
G01N 23/08(transferred to G01N 23/06, G01N 23/095)
G01N 23/083
•
•
•
the radiation being X-rays [2018.01]
G01N 23/085
•
•
•
•
X-ray absorption fine structure [XAFS], e.g. extended XAFS [EXAFS] [2018.01]
G01N 23/087
•
•
•
•
using polyenergetic X-rays [2006.01]
G01N 23/09
•
•
•
the radiation being neutrons [2018.01]
G01N 23/095
•
•
•
Gamma-ray resonance absorption, e.g. using the Mössbauer effect [2018.01]
G01N 23/10
•
•
•
the material being confined in a container, e.g. in luggage X-ray scanners [2018.01]
G01N 23/12
•
•
•
the material being a flowing fluid or a flowing granular solid [2018.01]
G01N 23/14(transferred to G01N 23/083-G01N 23/087, G01N 23/12)
G01N 23/16
•
•
•
the material being a moving sheet or film [2018.01]
G01N 23/18
•
•
•
Investigating the presence of defects or foreign matter [2018.01]
G01N 23/20
•
by using diffraction of the radiation by the materials, e.g. for investigating crystal structure; by using scattering of the radiation by the materials, e.g. for investigating non-crystalline materials; by using reflection of the radiation by the materials [2018.01]
G01N 23/20008
•
•
Constructional details of analysers, e.g. characterised by X-ray source, detector or optical system; Accessories therefor; Preparing specimens therefor (monochromators for X-rays using crystals G21K 1/06) [2018.01]
G01N 23/20016
•
•
•
Goniometers [2018.01]
G01N 23/20025
•
•
•
Sample holders or supports therefor [2018.01]
G01N 23/20033
•
•
•
•
provided with temperature control or heating means [2018.01]
G01N 23/20041
•
•
•
•
for high pressure testing, e.g. anvil cells [2018.01]
G01N 23/2005
•
•
•
Preparation of powder samples therefor [2018.01]
G01N 23/20058
•
•
Measuring diffraction of electrons, e.g. low energy electron diffraction [LEED] method or reflection high energy electron diffraction [RHEED] method [2018.01]
G01N 23/20066
•
•
Measuring inelastic scattering of gamma rays, e.g. Compton effect [2018.01]
G01N 23/20091
•
•
Measuring the energy-dispersion spectrum [EDS] of diffracted radiation [2018.01]
G01N 23/201
•
•
Measuring small-angle scattering, e.g. small angle X-ray scattering [SAXS] [2018.01]
G01N 23/202
•
•
•
using neutrons [2006.01]
G01N 23/203
•
•
Measuring back scattering [2006.01]
G01N 23/204
•
•
•
using neutrons [2006.01]
G01N 23/205
•
•
using diffraction cameras [2018.01]
G01N 23/2055
•
•
Analysing diffraction patterns [2018.01]
G01N 23/206(transferred to G01N 23/205)
G01N 23/22
•
by measuring secondary emission from the material [2018.01]
G01N 23/2202
•
•
Preparing specimens therefor [2018.01]
G01N 23/2204
•
•
Specimen supports therefor; Sample conveying means therefor [2018.01]
G01N 23/2206
•
•
Combination of two or more measurements, at least one measurement being that of secondary emission, e.g. combination of secondary electron [SE] measurement and back-scattered electron [BSE] measurement [2018.01]
G01N 23/2208
•
•
•
all measurements being of secondary emission, e.g. combination of SE measurement and characteristic X-ray measurement [2018.01]
G01N 23/2209
•
•
using wavelength dispersive spectroscopy [WDS] [2018.01]
G01N 23/221
•
•
by activation analysis [2006.01]
G01N 23/222
•
•
•
using neutron activation analysis [NAA] [2006.01]
G01N 23/223
•
•
by irradiating the sample with X-rays or gamma-rays and by measuring X-ray fluorescence [2006.01]
DG01N 23/225
•
•
using electron or ion microprobes [2018.01]
G01N 23/2251
•
•
•
using incident electron beams, e.g. scanning electron microscopy [SEM] [2018.01]
G01N 23/2252
•
•
•
•
Measuring emitted X-rays, e.g. electron probe microanalysis [EPMA] [2018.01]
G01N 23/2254
•
•
•
•
Measuring cathodoluminescence [2018.01]
G01N 23/2255
•
•
•
using incident ion beams, e.g. proton beams [2018.01]
G01N 23/2257
•
•
•
•
Measuring excited X-rays, i.e. particle-induced X-ray emission [PIXE] [2018.01]
G01N 23/2258
•
•
•
•
Measuring secondary ion emission, e.g. secondary ion mass spectrometry [SIMS] (mass-to-charge ratio analysis aspects of SIMS for material analysis G01N 27/62) [2018.01]
G01N 23/227
•
•
Measuring photoelectric effect , e.g. photoelectron emission microscopy [PEEM] [2018.01]
G01N 23/2273
•
•
•
Measuring photoelectron spectra, e.g. electron spectroscopy for chemical analysis [ESCA] or X-ray photoelectron spectroscopy [XPS] [2018.01]
G01N 23/2276
•
•
•
using the Auger effect, e.g. Auger electron spectroscopy [AES] [2018.01]