Abstract: A stock carton knife including a handle and a blade projecting from the handle and having two lateral edges and an outer end. The blade has a lateral cutting notch in one of the lateral edges, the cutting notch having a laterally oriented mouth including an inner edge closer to the handle and an outer edge farther from the handle. The outer edge converges with the outer end to form a juncture. The juncture has a configuration which includes at least one lateral recess. The safety carton knife further includes a blunt knob bonded on the juncture by a bonding material which is in the least one recess, thereby securing the knob to the blade.

Abstract: A method and apparatus for accurately observing a toric contact lens rotation for determining the prescription of a contact lens on an astigmatic eye, by providing a lens line guide alignment plate having a gravity responsive pivotal indicator, angle indicia arranged about the indicator, and a guide edge spaced from the indicator, a contact lens having at least one indicator marking, a slit lamp or other device for projecting a slit light beam on the lens to bisect the lens, rotationally orienting the slit light beam into alignment with the contact lens indicator marking, angularly orienting the guide edge to be in alignment with the rotated slit light beam, and reading the angle of the pivotal indicator relative to the indicia to ultimately determine the toric lens prescription.

Abstract: An optical diagnostic apparatus for measuring toric contact lens rotation comprising a slit lamp optical instrument including a light source, a slit light projector for projecting a beam of light, and a slit light rotator for rotating the beam of light, a patient head retainer in alignment with the projector to project a slit light beam from the projector onto the eye of a patient and a contact lens on the eye, a slit light rotator actuator for the slit light rotator, for rotating the projected slit light over a range of angles onto the patient's eye and the contact lens thereon, a gravity responsive angle indicator and/or electronic indicator at the slit light rotator, and an arcuate angle scale rotatable with the slit light rotator and cooperable with the indicator to indicate angle of rotation of the angle scale and rotator, whereby the contact lens toric angle can be observed for determining the toric contact lens prescription.

Abstract: A stock carton knife comprising an elongated handle having a pair of ends, a blade projecting from one end of the handle and having two lateral edges and an outer end, a lateral cutting notch in one of the lateral edges having a sharpened cutting edge and a laterally oriented mouth and including an inner sharp edge closer to the handle and an outer sharp edge farther away from the handle, the outer edge converging with the blade end to form a juncture with a blunt knob, the mouth being smaller in width than about one centimeter, and a diagonal guard plate on the blade along the inner edge, normal to and astraddle of the blade, with a first surface area toward the handle to protect the fingers of a user, and a second surface area toward the notch to limit depth of cut by the blade into a carton.

Abstract: A stock carton knife comprising an elongated handle having a pair of ends, a blade projecting from one end of the handle and having two lateral edges and an outer end, a lateral cutting notch in one of the lateral edges having a sharpened cutting edge and a laterally oriented mouth and including an inner sharp edge closer to the handle and an outer sharp edge farther away from the handle, the outer edge converging with the blade end to form a juncture with a blunt knob, the mouth being smaller in width than about one centimeter, and a diagonal guard plate on the blade along the inner edge, normal to and astraddle of the blade, with a first surface area toward the handle to protect the fingers of a user, and a second surface area toward the notch to limit depth of cut by the blade into a carton.