Changeable compass colours for improved viewing
OwnerPaul CHAPMANinventor
Life of this patent
Estimating the term…
Abstract
A lighting and colour scheme for instruments to allow an apparent colour change of indicia and background between daylight viewing and night-time viewing when an instrument light is turned on. White indicia on a red background is conspicuous in daytime, but can be transformed to green indicia on black background when the instrument is illuminated with a green LED for night-time viewing.
Claims12
A magnetic compass having indicia and background having at least two contrasting opaque colours and a lighting element for nocturnal use, characterised by indicia in a first colour and a background in a second colour that has a reflective spectrum that features a band of substantially total absorption, said lighting element having an emission spectrum with one or more peaks which fall within the absorption band of the second colour and is within the reflective spectral bands of the first colour.
A magnetic compass comprising:
- a dial and a pointer which rotate relative to one another, the dial having indicia of a first opaque colour and a background having contrasting second opaque colour when viewed in daylight, the second opaque colour having a reflective spectrum that features a band of substantially total absorption, and
- a lighting element for use in low daylight conditions, the lighting element having a limited colour spectrum falling substantially within a band of substantially total absorption of the dial and which is within the reflective spectral band of the first colour,
- wherein, when the dial is illuminated by the lighting element, the indicia reflects light and are visible while the background absorbs light and appears to be black.
Dependencies are inferred from the claim text.