Method, device and cartridge for measuring fluctuations in the cross-sectional area of hair in a pre-determined scalp area

A two-part cartridge for use in measuring a bundle of hair isolated from the scalp, said cartridge comprising a first, larger, generally rectangular part having a top and a bottom and four sides with a rectangular in cross section slot extending into the first part from one side thereof, said first part having a transverse first slit traversing the slot and extending though the top and bottom of the first part and extending inwardly from the one side of the first part, a second, smaller, rectangular part having a generally rectangular cross section with the same shape and size as the cross section of the slot in the first part and adapted to be received in said slot, said second part having an inner end and an outer end with a second slit extending transversely through the second part from the inner end, said second slit having approximately the same width as the first slit and is adapted to mate with the first slit in the first part when the second part is inserted into the slot in the first part.

The cartridge of claim 11 wherein an elongated side of said smaller second part and a wall of said slot in said first part have cooperating detent and recess structure which engage when the second part is pulled part way out of the first part.

A device for measuring the mass of a bundle of hair isolated from a predetermined location on a scalp, said device comprising a body, said body having a first end and a second end, a plunger extending through said body, said plunger having an L shaped end extending from said first end of said body and a plunger outer portion extending from said second end and having a knob at the outer end thereof, a spring between said knob and said body on said outer portion of said plunger, a gauge on said body for measuring the movement of said L shaped arm toward said first end of said body, structure having a changeable length slit therein adapted to be mounted on said L shaped arm when said L shaped arm is extended, said structure being manipulated to gather a bundle of hair in said changeable length slit, said knob then being pushed to extend said L shaped arm to mount said structure thereon followed by said knob being released so that said spring acting between the second end of the body and said knob cause said L shaped arm to push said structure towards said first end of said body to cause the bundle of hair to be compressed in said changeable length slit and the height of the bundle of hair in said changeable length slit being measured by said gauge on said body.