|  | G |
SECTION G — PHYSICS

|  | G |
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, appearing in the notes of several of the classes in this section, in particular those of "measuring" in class Fulltext... Hierarchy... Expanded...G01 and "control" and "regulation" in class Fulltext... Hierarchy... Expanded...G05. 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 (Fulltext... Hierarchy... Expanded...G09), for enabling the result of a measurement to be known (Fulltext... Hierarchy... Expanded...G01), for signalling the information to a distant point or for giving information which has been signalled from a distant point (Fulltext... Hierarchy... Expanded...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 (Fulltext... Hierarchy... Expanded...G01L) or about some other condition linked to the pressure (another subclass of class Fulltext... Hierarchy... Expanded...G01, e.g., Fulltext... Hierarchy... Expanded...G01K for temperature), to make a record of the pressure or of its occurrence (Fulltext... Hierarchy... Expanded...G07C), to give an alarm (Fulltext... Hierarchy... Expanded...G08B), or to control another apparatus (Fulltext... Hierarchy... Expanded...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

|  | G02 |
OPTICS (making optical elements or apparatus Fulltext... Hierarchy... Expanded...B24B, Fulltext... Hierarchy... Expanded...B29D 11/00, Fulltext... Hierarchy... Expanded...C03, or other appropriate subclasses or classes; materials per se, see the relevant places, e.g. Fulltext... Hierarchy... Expanded...C03B, Fulltext... Hierarchy... Expanded...C03C)

|  | G02 |
Note(s) In this class, the following expression is used with the meaning indicated: "optical" applies not only to visible light but also to ultra-violet or infra-red radiations. [4]

|  | G02C |
SPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES (trial frames for testing the eyes Fulltext... Hierarchy... Expanded...A61B 3/04; goggles or eyeshields not having the same features as spectacles Fulltext... Hierarchy... Expanded...A61F 9/00)

|  | G02C |
Note(s) This subclass covers also contact lenses for the eyes, monocles, pince-nez, or lorgnettes.

|  | G02C |
Subclass index
OPTICAL PARTS | 7/00
NON-OPTICAL PARTS |
Supporting arrangements; adjuncts | 3/00, 5/00; 11/00
ATTACHMENTS OF OPTICAL PARTS TO NON-OPTICAL PARTS |
Principal; auxiliary | 1/00; 9/00
ASSEMBLING, REPAIRING, CLEANING | 13/00

|  | G02C 1/00 |
Assemblies of lenses with bridges or browbars

|  | G02C 1/02 |
· | Bridge or browbar secured to lenses without the use of rims

|  | G02C 1/04 |
· | Bridge or browbar secured to, or integral with, partial rims, e.g. with partially-flexible rim for holding the lens

|  | G02C 1/06 |
· | Bridge or browbar secured to, or integral with, closed rigid rims for the lenses

|  | G02C 1/08 |
· · | the rims being transversely-split and provided with securing means

|  | G02C 3/00 |
Special supporting arrangement for lens assemblies or monocles (lenses therefor Fulltext... Hierarchy... Expanded...G02C 7/00)

|  | G02C 3/02 |
· | Arrangements for supporting by headgear

|  | G02C 3/04 |
· | Arrangements for supporting by hand, e.g. lorgnette; Arrangements for supporting by articles (by walking-sticks Fulltext... Hierarchy... Expanded...A45B 3/00)

|  | G02C 5/00 |
Constructions of non-optical parts

|  | G02C 5/02 |
· | Bridges; Browbars; Intermediate bars (nose-engaging surfaces Fulltext... Hierarchy... Expanded...G02C 5/12)

|  | G02C 5/04 |
· · | with adjustable means

|  | G02C 5/06 |
· · | with resilient means

|  | G02C 5/08 |
· · | foldable

|  | G02C 5/10 |
· · | Intermediate bar or bars between bridge and side-members

|  | G02C 5/12 |
· | Nose-pads; Nose-engaging surfaces of bridges or rims

|  | G02C 5/14 |
· | Side-members

|  | G02C 5/16 |
· · | resilient or with resilient parts

|  | G02C 5/18 |
· · | reinforced

|  | G02C 5/20 |
· · | adjustable, e.g. telescopic

|  | G02C 5/22 |
· | Hinges (pivotal connection in general Fulltext... Hierarchy... Expanded...F16C 11/00)

|  | G02C 7/00 |
Optical parts (characterised by the material Fulltext... Hierarchy... Expanded...G02B 1/00)

|  | G02C 7/02 |
· | Lenses; Lens systems

|  | G02C 7/04 |
· · | Contact lenses for the eyes

|  | G02C 7/06 |
· · | bifocal; multifocal

|  | G02C 7/08 |
· · | Auxiliary lenses; Arrangements for varying focal length

|  | G02C 7/10 |
· | Filters, e.g. for facilitating adaptation of the eyes to the dark; Sunglasses

|  | G02C 7/12 |
· | Polarisers

|  | G02C 7/14 |
· | Mirrors; Prisms

|  | G02C 7/16 |
· | Shades, shields; Obturators, e.g. with pinhole, with slot

|  | G02C 9/00 |
Attaching auxiliary optical parts (auxiliary optical parts Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...G02C 7/08-G02C 7/16)

|  | G02C 9/02 |
· | by hinging

|  | G02C 9/04 |
· | by fitting over or clamping on

|  | G02C 11/00 |
Non-optical adjuncts; Attachment thereof (Fulltext... Hierarchy... Expanded...G02C 7/16 takes precedence; cases Fulltext... Hierarchy... Expanded...A45C 11/04)

|  | G02C 11/02 |
· | Ornaments, e.g. exchangeable

|  | G02C 11/04 |
· | Illuminating means

|  | G02C 11/06 |
· | Hearing aids (construction of hearing aids Fulltext... Hierarchy... Expanded...H04R 25/00)

|  | G02C 11/08 |
· | Anti-misting means, e.g. ventilating, heating (Fulltext... Hierarchy... Expanded...H05B 3/84 takes precedence); Wipers [5]

|  | G02C 13/00 |
Assembling (producing spectacle frames from plastics or from substances in a plastic state Fulltext... Hierarchy... Expanded...B29D 12/02); Repairing; Cleaning