http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-698058-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_5331928db107ef1c363d166cad8a2edb |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/G02B5-285 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G02B5-28 |
| filingDate | 1951-05-28-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1953-10-07-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-698058-A |
| titleOfInvention | Improvements in optical interference filters |
| abstract | 698,058. Interference filters. SCHROEDER, H. May 28, 1951 [Oct. 1, 1948], No. 12466/51. Class 97 (i). A filter comprises one or more transparent bodies, the or each body having on at least one surface thereof an infra-red reflecting system of layers, said system comprising at least two non-metallic layers alternately of high and low refractive index materials, the optical thickness of each layer being about onequarter of that wavelength in the infra-red region which is to be least transmitted and also about one-half of the wave-length at the centre of the visible spectrum, and wherein differences exist between the optical thicknesses of at least one low refractive layer and at least one high refractive layer, such differences preferably being not greater than 20 per cent. Fig. I shows a filter which transmits least the wavelength 10,000 Š. It comprises a transparent support 10, layers 12, 14 and 16 of zinc sulphide, and layers 13, 15 and 17 of magnesium fluoride. The zinc sulphide layers have a thickness about one-half of the wavelength 5500A and the layers 13, 15 are approximately each of a thickness equal to seven-sixteenths of that wavelength. To provide high transmission in the visible region, layer 17 is of a thickness equal to one-quarter of the wavelength 5500Š. Preferably two systems of interference layers are used, each system having layers of optical thickness different from those of the other system. Calcium fluoride, or cryolite may also be used for the low index layers while lead chloride, thallium chloride or silver chloride may be used for the high index layers. A spectral reflection curve is given in the Specification. |
| priorityDate | 1948-10-01-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 24.