GB2057159A - Rear-view optical system - Google Patents

Abstract

A rear-view optical system 2 mountable on a motorcyclist's helmet 1 or other headgear, comprises first, second and third mirrors 3,4,5 arranged in succession between objective and viewing ends of the system, and arranged to reflect light, incident from the rear, from the first to the second to the third mirrors in succession, over the top of the wearer's head and into his eyes. Preferably mirror 3 is convex and mirrors 4,5 are planar. Mirror 5 may be adjustable and may have a shield to avoid dazzle. <IMAGE>

Description

SPECIFICATION Rear-view optical system This invention relates to a rear-view optical system provided on or mountable on a helmet or other type of headgear to give the wearer a view rearwards.

A clear rearward view is required for motorcyclists, but is also often required for under-water work. In accordance with this invention, there is provided a rear-view optical system provided on or mountable on a helmet or other type of headgear, comprising fist, second and third mirrors arranged in succession between objective and viewing ends of the system, and arranged to reflect light, incident from the rear of a wearer of the helmet or headgear, from the first to the second to the third mirrors in succession, over the top of the wearer's head and into his eyes. Thus, the optical system extends up over the top of the helmet or headgear and the wearer obtains his rear view by lifting his eyes to look into the front end of the system, the rear end being directed, generally horizontally, in the rearwards direction.

An embodiment of this invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a vertical section through a rear-view optical system applied to a motorcyclist's helmet; Figure 2 is a front view of the system applied to the helmet; and Figure 3 is a plan view of the system.

Referring to the drawings, there is shown a motorcyclist's helmet 1 provided with a rear-view optical system 2, extending up and over the top of the helmet. The optical system comprises first, second and third mirrors 3, 4, 5 only, arranged in succession bet veen objective and viewing ends 6, 7 of the system, .,nd mounted in a tubular casing 8 which is removably mounted on the outer side of the helmet to extend up and over the top of the helmet.

The under side of the casing is curved to complemenu the contours of the helmet. The opposite ends of the tubular casing 8 are closed by transparent windows 9, 10: window 9 is directed generally rearwardly and window 10 is directed generally into the eyes of the wearer of the helmet. The mirrors are each rectangular, with their longer sides extending transverse of the helmet, and mirror 3 is convex whilst mirrors 4 and 5 are planar: all three are mirror-coated on their front surfaces.

Light incident from the rear passes through window 9 and is reflected from mirror 3 to mirror 4 to mirror 5 in succession and then into the wearer's eyes through window 10 to provide the wearer with an erect image of the rearward view. Thus, light generally horizontally incident upon mirror 3 is reflected generally downwards and forwards onto mirror 4 and then generally downwards into mirror 5 and finally rearwardly and downwardly into the eyes.

The viewing mirror 5 may be mounted for adjustment about a horizontal axis transverse of the helmet. A shield may be provided for this mirror and operated by the wearer when desired to close off the rearward view and avoid dazzle.

1. A rear-view optical system provided on or mountable on a helmet or other type of headgear, comprising first, second and third mirrors arranged in succession between objective and viewing ends of the system, and arranged to reflect light, incident from the rear of a wearer of the helmet or headgear, from the first to the second to the third mirrors in succession, over the top of the wearer's head and into his eyes.

2. A rear-view optical system as claimed in claim 1, in which the mirrors are mounted within a tubular casing extending between objective and viewing ends or the system.

3. A rear-view optical system as claimed in claim 2, in which the opposite ends of the tubular casing are closed by transparent windows.

4. A rear-view optical system as claimed in claim 2 or 3, in which the tubular casing is removably mounted or mountable on the outer side of the helmet or headgear.

5. A rear-view optical system as claimed in any preceding claim, in which the first mirror is a convex mirror.

6. A rear-view optical system as claimed in any preceding claim, in which the third mirror is mounted for adjustment about a horizontal axis transverse of the helmet or headgear.

7. A rear-view optical system as claimed in any preceding claim, further comprising a shield for the third mirror and operable to close off the rearward view.

8. A rear-view optical system substantially as herein described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Rear-view optical system This invention relates to a rear-view optical system provided on or mountable on a helmet or other type of headgear to give the wearer a view rearwards. A clear rearward view is required for motorcyclists, but is also often required for under-water work. In accordance with this invention, there is provided a rear-view optical system provided on or mountable on a helmet or other type of headgear, comprising fist, second and third mirrors arranged in succession between objective and viewing ends of the system, and arranged to reflect light, incident from the rear of a wearer of the helmet or headgear, from the first to the second to the third mirrors in succession, over the top of the wearer's head and into his eyes. Thus, the optical system extends up over the top of the helmet or headgear and the wearer obtains his rear view by lifting his eyes to look into the front end of the system, the rear end being directed, generally horizontally, in the rearwards direction. An embodiment of this invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a vertical section through a rear-view optical system applied to a motorcyclist's helmet; Figure 2 is a front view of the system applied to the helmet; and Figure 3 is a plan view of the system. Referring to the drawings, there is shown a motorcyclist's helmet 1 provided with a rear-view optical system 2, extending up and over the top of the helmet. The optical system comprises first, second and third mirrors 3, 4, 5 only, arranged in succession bet veen objective and viewing ends 6, 7 of the system, .,nd mounted in a tubular casing 8 which is removably mounted on the outer side of the helmet to extend up and over the top of the helmet. The under side of the casing is curved to complemenu the contours of the helmet. The opposite ends of the tubular casing 8 are closed by transparent windows 9, 10: window 9 is directed generally rearwardly and window 10 is directed generally into the eyes of the wearer of the helmet. The mirrors are each rectangular, with their longer sides extending transverse of the helmet, and mirror 3 is convex whilst mirrors 4 and 5 are planar: all three are mirror-coated on their front surfaces. Light incident from the rear passes through window 9 and is reflected from mirror 3 to mirror 4 to mirror 5 in succession and then into the wearer's eyes through window 10 to provide the wearer with an erect image of the rearward view. Thus, light generally horizontally incident upon mirror 3 is reflected generally downwards and forwards onto mirror 4 and then generally downwards into mirror 5 and finally rearwardly and downwardly into the eyes. The viewing mirror 5 may be mounted for adjustment about a horizontal axis transverse of the helmet. A shield may be provided for this mirror and operated by the wearer when desired to close off the rearward view and avoid dazzle. CLAIMS

1. A rear-view optical system provided on or mountable on a helmet or other type of headgear, comprising first, second and third mirrors arranged in succession between objective and viewing ends of the system, and arranged to reflect light, incident from the rear of a wearer of the helmet or headgear, from the first to the second to the third mirrors in succession, over the top of the wearer's head and into his eyes.

2. A rear-view optical system as claimed in claim 1, in which the mirrors are mounted within a tubular casing extending between objective and viewing ends or the system.

3. A rear-view optical system as claimed in claim 2, in which the opposite ends of the tubular casing are closed by transparent windows.

4. A rear-view optical system as claimed in claim 2 or 3, in which the tubular casing is removably mounted or mountable on the outer side of the helmet or headgear.

5. A rear-view optical system as claimed in any preceding claim, in which the first mirror is a convex mirror.

6. A rear-view optical system as claimed in any preceding claim, in which the third mirror is mounted for adjustment about a horizontal axis transverse of the helmet or headgear.

7. A rear-view optical system as claimed in any preceding claim, further comprising a shield for the third mirror and operable to close off the rearward view.

8. A rear-view optical system substantially as herein described with reference to the accompanying drawings.