Abstract: Disclosed is a propeller having at least first and second blade assemblies located one above the other. Each of the blade assemblies has a plurality of blades that extend radially outward from a shaft. The shaft can be coupled to a suitable land, sea or air vehicle (e.g., a ship). The blades of the first blade assembly lie above and alternate out of phase with the blades of the second blade assembly. Each of the blades of the first and second blade assemblies slopes downwardly relative to the shaft such that the leading sides thereof are located lower along the shaft than the opposite trailing sides. The blades of the first blade assembly are aligned with respective ones of the blades of the second blade assembly to establish substantially continuous and long downwardly sloping surface areas capable of maximizing the propulsion force generated by the propeller.

Abstract: The head of a golf iron having an improved profile that enables a golfer to accurately align the club head with a golf ball so that the club head will strike the ball at the sweet spot located on the club face. The club head has a top edge which runs above the club face and includes first and second portions that extend in first and second directions. The boundary line between the first and second portions at the top edge of the club head lies in a vertical sweet spot reference plane with the center of the sweet spot. The boundary line at the top edge of the club head is visible to the golfer looking down at his club head so as to provide the golfer with an indication of the location of the sweet spot on the club face at which to strike the golf ball during his swing.

Abstract: A windmill blade assembly that is rotated in response to the wind. Each of a first and a second blade member has first and opposite ends and a hub mounting hole located between the ends. The first blade member is located above the second blade member such that the hub mounting holes thereof are axially aligned to receive a hub therethrough. The first and second blade members are turned along the hub or bent so as to provide a pitch that is aerodynamically configured to cause the rotatable blade assembly to spin. The windmill blade assembly is connected by a correspondingly rotatable shaft which extends from the hub thereof to an electrical power generator.

Abstract: The head of a golf iron having an improved profile that enables a golfer to accurately align the club head with a golf ball so that the club head will strike the ball at the sweet spot located on the club face. The club head has a top edge which runs above the club face and includes first and second portions that extend in first and second directions. The boundary line between the first and second portions at the top edge of the club head lies in a vertical sweet spot reference plane with the center of the sweet spot. The boundary line at the top edge of the club head is visible to the golfer looking down at his club head so as to provide the golfer with an indication of the location of the sweet spot on the club face at which to strike the golf ball during his swing.

Abstract: An optical toy adapted to enable a user, such as a child, to see a 3-dimensional image that is representative of an object being held in front of the toy. The toy includes a frame which surrounds a set of optical components and an optical components carrier. The set of optical components of the toy includes an optically-transparent (e.g., convex) lens and a reflective (e.g., concave) mirror surface that is located behind the transparent lens. The optical components carrier to which the set of optical components of the toy is attached is removable from the rear of the frame to be replaced by a different carrier having a different set of optical components.

Abstract: A device having a pair of blades spinnable about a spin axis. The pair of blades includes a first blade and a second blade, with the first blade canted about a first-blade canting axis at a first-blade canting angle and the second blade canted about a second-blade canting axis at a second-blade canting angle. The first-blade canting axis is oriented at a first-blade canting axis angle relative to a first-blade radial and the second-blade canting axis is oriented at a second-blade canting axis angle relative to a second-blade radial, each canting axis angle being other than 90 degrees. The first-blade radial is oriented perpendicular to a first chord plane that passes through the first blade and contains a first-blade chord, and the second-blade radial is oriented perpendicular to a second chord plane that passes through the second blade and contains a second-blade chord.

Abstract: An optical system is provided for magnifying the image on a television receiver to viewers in a room. The system is comprised of a plano-convex lens disposed in front of the viewing screen of a television set and a fresnel lens interposed between the viewing screen and the plano-convex lens. The fresnel lens has a smooth surface and an opposite surface configured with a pattern of concentric dioptric ridges facing the plano-convex lens. The magnification achieved by the combination of lenses allows viewers within the room to view a magnified image on the television receiver. Preferably, the planar surface of the plano-convex lens and the smooth surface of said fresnel lens are both disposed to face the television screen so that the television screen can be viewed without significant aberrations or distortion from a wide range of viewing distances.