Abstract: The invention provides a variable focus lens formed from a ring with a front surface and a rear surface, a flexible membrane is attached to a radially inner part of the front surface, and a front cover is attached to a radially outer part of the front surface, a rear cover is provided on the rear surface of the ring, preferably integral with the ring, so that a variable volume cavity is defined between the flexible membrane, the ring and the rear cover, second flexible membrane can be provided between the ring and the rear cover, where the invention also provides a method of filling a variable focus lens, and an adjustment mechanism for varying the focus of the lens.

Abstract: The invention provides a variable focus lens formed from a ring with a front surface and a rear surface, a flexible membrane is attached to a radially inner part of the front surface, and a front cover is attached to a radially outer part of the front surface, a rear cover is provided on the rear surface of the ring, preferably integral with the ring, so that a variable volume cavity is defined between the flexible membrane, the ring and the rear cover, second flexible membrane can be provided between the ring and the rear cover, where the invention also provides a method of filling a variable focus lens, and an adjustment mechanism for varying the focus of the lens.

Abstract: A variable focus lens includes a ring with a front surface and a rear surface. A flexible membrane is held between the front surface of the ring and a generally rigid transparent front cover, and a rear cover is attached to the rear surface of the ring, optionally with a second flexible membrane sandwiched between the rear cover and the ring. A cavity is formed between the flexible membrane and the rear cover or the second flexible membrane is filled with a liquid, and the amount of fluid in the cavity can be varied to vary the curvature of the flexible membrane and so vary the optical characteristics of the lens. The ring of the lens may be coloured, and may be transparent, translucent or opaque. Alternatively, a decorative cover may be attached to the front of the ring to give the appearance of a frame. The lenses may be used in variable focus spectacles.

Abstract: The invention relates to a variable focus lens (10), comprising a rigid ring (22), a flexible membrane (20) attached to the front surface of the ring, a rigid transparent front cover (40), attached to the flexible membrane (50), and a rigid rear cover (20) on the rear surface of the ring (22). A cavity (60) is formed between the flexible membrane (50) and the rear cover (20), and the cavity is filled with a liquid. The amount of liquid in the cavity can be varied to vary the curvature of the flexible membrane and so vary the optical characteristics of the lens. The rear cover can be integral with the ring, or formed separately. Further, a second flexible membrane can be positioned between the rear cover and the ring. The various parts of the lens can be held together by adhesive.

Abstract: The invention relates to a variable focus lens (10), comprising a rigid ring (22), a flexible membrane (20) attached to the front surface of the ring, a rigid transparent front cover (40), attached to the flexible membrane (50), and a rigid rear cover (20) on the rear surface of the ring (22). A cavity (60) is formed between the flexible membrane (50) and the rear cover (20), and the cavity is filled with a liquid. The amount of liquid in the cavity can be varied to vary the curvature of the flexible membrane and so vary the optical characteristics of the lens. The rear cover can be integral with the ring, or formed separately. Further, a second flexible membrane can be positioned between the rear cover and the ring. The various parts of the lens can be held together by adhesive.

Abstract: The invention provides a variable focus lens, comprising a ring with a front surface and a rear surface. A flexible membrane is held between the front surface of the ring and a generally rigid transparent front cover, and a rear cover is attached to the rear surface of the ring (optionally with a second flexible membrane sandwiched between the rear cover and the ring). A cavity is formed between the flexible membrane and the rear cover (or the second flexible membrane) is filled with a liquid, and the amount of fluid in the cavity can be varied to vary the curvature of the flexible membrane and so vary the optical characteristics of the lens. The ring of the lens may be coloured, and may be transparent, translucent or opaque. Alternatively, a decorative cover may be attached to the front of the ring to give the appearance of a frame. The lenses may be used in variable focus spectacles.

Abstract: A variable focus lens (10) comprises a ring (20) with a front surface and a rear surface. A flexible membrane (40) is held between the front surface of the ring and a generally rigid transparent front cover (50), and a rear cover (60) is mounted on the rear surface of the ring, such that a cavity formed between the flexible membrane and the rear cover can be filled with a liquid. The amount of fluid in the cavity can be varied to vary the curvature of the flexible membrane and so vary the optical characteristics of the lens. The ring is provided with an integral hollow extension (22), whose hollow interior (24) communicates with the cavity and forms a liquid reservoir for the variable focus lens (10). The invention also extends to spectacles using the lens.

Abstract: The invention relates to a variable focus lens (10), comprising a rigid ring (22), a flexible membrane (20) attached to the front surface of the ring, a rigid transparent front cover (40), attached to the flexible membrane (50), and a rigid rear cover (20) on the rear surface of the ring (22). A cavity (60) is formed between the flexible membrane (50) and the rear cover (20), and the cavity is filled with a liquid. The amount of liquid in the cavity can be varied to vary the curvature of the flexible membrane and so vary the optical characteristics of the lens. The rear cover can be integral with the ring, or formed separately. Further, a second flexible membrane can be positioned between the rear cover and the ring. The various parts of the lens can be held together by adhesive.