RANGER-FINDER IN A TELESCOPIC SIGHT

• US 3,684,376 A
• Filed: 09/10/1970
• Issued: 08/15/1972
• Est. Priority Date: 09/10/1970
• Status: Expired due to Term

• Current Assignee: Donald E. Lessard
• Original Assignee: Donald E. Lessard
• Inventors: Lessard, Donald E.
• Primary Examiner(s): Wibert, Ronald L.
• Assistant Examiner(s): Chew, II, Orville B.
• Application Number:
  US05/071,020
• Time in Patent Office: 705 Days
• Field of Search: 33/5A 350/10 356/21
• US Class Current: 356/21
• CPC Class Codes: G01C 3/04 Adaptation of rangefinders for combination with telescopes or binoculars

Abstract

This invention relates to a range-indicating, variable-power telescopic sight; based on the principle of comparing adjustable spaced reference elements, with known target dimensions, reading said comparison on a scale of distance. More specifically, nonmagnifying reference elements positioned within the optical system in a variable-power telescope at the rearward focal plane are superimposed upon the image of the target object and the size of the target object is altered by manually varying the degree of magnification of said target object until such target object is bracketed just between the spaced reference elements. A scale of target object distance, also within the optical system, positioned at the rearward focal plane, operativly connected to the means of varying the degree of magnification of the target object and correlated with the various degrees of magnification shows the distance to the target object once the foregoing condition is achieved.

Claims

1. A range-finder in a telescopic sight which comprises;

a main body tube, objective lens located at the forward end of the tube body, erector lens means mounted in the tube body for axial movement therein, adapted to produce an erect image of a target object, which axial movement varies the degree of magnification of the target object, a forward focal plane spaced forward thereof, eyepiece lens means located at the rearward end of the tube body adapted to focus upon the erect image of the target object, reticle means mounted in the tube body at a rear focal plane capable of being superimposed upon the target object, and carrying fixed aiming elements, and spaced reference elements for bracketing a variety of known dimensions of target objects, one of said reference elements which is fixed, and the other of said reference elements which is manually selectively adjustable in relationship to said fixed reference element, to accommodate the bracketing of the desired portion of a target object, of a variety of sizes of target objects, between said fixed reference element and said manually selectively adjustable reference element, said bracketing of the target object accomplished through varying the degree of magnification of the target object in the forward focal plane, comparing same with the non-magnified reference elements positioned in the rearward focal plane, indexing means with target object size indicating indicia for said manually selectively adjustable reference element, scale means of target object distance indicating indicia at a rear focal plane for viewing through the telescopic sight, operatively connected to the means of magnification variance and correlated With the changes in the degree of magnification of the target object, with the target object simultaniously bracketed between the spaced reference elements, a window at the rear focal plane for viewing of the target object distance indicating indicia.

2. A range-finder in a telescopic sight as set forth in claim 1 in which;

spaced reference elements are provided for bracketing of the target object, one of said reference elements which is fixed, and the other of said reference elements which is manually selectively adjustable for varying the spacing between said fixed reference element and said selectively adjustable reference element with indexing means and target object size indicating indicia provided therefore.

3. A range-finder in a telescopic sight as set forth in claim 1 in which;

target object distance indicating indicia is provided for viewing through the telescopic sight, said distance indicating indicia being operatively connected to the means of manually varying the degree of magnification of the target object and correlated with the varying degrees of magnification.

4. A range-finder in a telescopic sight as set forth in claim 1 in which;

a window is provided for viewing of the target object distance indicating indicia in the telescopic sight while simultaniously viewing the target object bracketed between the spaced reference elements.

5. A method of ascertaining the distance to a variety of target object sizes of known dimensions including the steps of:

providing spaced reference elements for bracketing a known dimension of a target object, providing means of manually setting the other of said reference elements in spacing relationship to said fixed reference element with said spacing indicating indicia provided therefore, providing a scale of target object distance indicating indicia for viewing through the telescopic sight, providing a window for viewing of the target object distance indicating indicia in the telescopic sight;

whereby the user may first select the desired spacing of the reference elements, determined by a known dimension of the selected target object, bracket the desired portion of the target object between the spaced reference elements by viewing the target object through the telescopic sight and manually changing the degree of magnification of the target object until said target object will fit just between the spaced reference elements and then may note the distance to the target object through the viewing window, as indicated by the target object distance indicating indicia viewed therein.