Statements (23)
| Predicate | Object |
|---|---|
| gptkbp:instanceOf |
Lens
|
| gptkbp:category |
Lens
|
| gptkbp:diameter |
approximately 2.59 meters
|
| gptkbp:height |
920 mm
about 2.59 meters |
| https://www.w3.org/2000/01/rdf-schema#label |
First Order Fresnel lens
|
| gptkbp:introducedIn |
1820s
|
| gptkbp:inventedBy |
gptkb:Augustin-Jean_Fresnel
|
| gptkbp:material |
gptkb:glass
|
| gptkbp:notableExample |
gptkb:Pigeon_Point_Lighthouse
gptkb:Cape_Hatteras_Lighthouse gptkb:Makapu'u_Point_Lighthouse |
| gptkbp:order |
first
|
| gptkbp:purpose |
to focus light into a powerful beam
|
| gptkbp:replacedBy |
modern electric beacons
|
| gptkbp:size |
largest Fresnel lens order
|
| gptkbp:usedFor |
aiding navigation
increasing lighthouse visibility |
| gptkbp:usedIn |
lighthouses
major seacoast lighthouses |
| gptkbp:weight |
up to several tons
|
| gptkbp:bfsParent |
gptkb:St._Augustine_Lighthouse
|
| gptkbp:bfsLayer |
6
|