Lighted nock

1. A lighted nock comprising:

a light emitting unit including a light and a cylindrical battery, wherein the light is turned on or off by moving the light toward the battery or away from the battery;

a shaft adaptor which includes a cylindrical structure so that an outer surface is inserted into a rear end of a shaft, in which the battery is inserted into an inner space of the shaft adaptor; and

a light operator which is inserted in an upper portion of the shaft adaptor, while a lower portion of the light operator receives the light,

wherein the light is turned on or off by moving the light operator toward or away from the shaft adaptor, and

wherein the light operator includes a raised first registration feature and the shaft adaptor includes a recessed second registration feature that is complimentary to the raised first registration feature such that the light operator cannot rotate relative to the shaft adaptor when the light operator is moved toward or away from the shaft adaptor.

2. The lighted nock of claim 1 , wherein the light operator is a nock body, wherein the raised first registration feature is an index tab, wherein the recessed second registration feature is an index slot, and wherein the index slot extends longitudinally along an interior surface of the shaft adaptor.

3. The lighted nock of claim 1 , wherein the shaft is a crossbow arrow shaft.

4. A lighted nock assembly, comprising:

an LED/battery assembly, including an LED and a battery;

a nock housing which includes a cylindrical structure so that an outer surface is inserted into a rear end of a shaft, wherein a portion of the LED/battery assembly is disposed within the nock housing; and

a nock body linearly movable towards and away from the nock housing, wherein a portion of the LED/battery assembly is secured within the nock body such that moving the nock body away from the nock housing along a straight line turns the LED from a lighted state to an unlighted state,

wherein the nock body includes a raised registration feature configured to prevent the nock body from rotating about its major axis while moving along the straight line.

5. The lighted nock assembly of claim 4 wherein the raised registration feature further prevents the nock body from rotating about its major axis with respect to the nock housing while the nock body is moved away from the nock housing along the straight line.

6. The lighted nock assembly of claim 4 wherein the raised registration feature further prevents the nock body from rotating about its major axis with respect to the shaft while the nock body is moved away from the nock housing along the straight line.

7. The lighted nock assembly of claim 4 , wherein the raised registration feature is a guide protrusion projecting radially outwardly from an outer circumferential surface of the nock body.

8. The lighted nock assembly of claim 7 , wherein the raised registration feature is longitudinally elongated and aligned with a longitudinal axis of the nock housing.

9. The lighted nock assembly of claim 4 , wherein the raised registration feature is located on a forwardly protruding portion of the nock body.

10. The lighted nock assembly of claim 9 , wherein nock body defines a rear portion that has a larger diameter than the forwardly protruding portion.

11. The lighted nock assembly of claim 9 , wherein the rear portion defines a channel configured to accept a bow string.

12. The lighted nock assembly of claim 4 , wherein the shaft is a crossbow arrow shaft.

13. A method of operating a lighted nock, the lighted nock including a nock body, nock receiver, LED and battery, the method comprising:

moving the nock body in a linear motion towards the nock receiver to turn on the LED;

moving the nock body in a linear motion away from the nock receiver to turn off the LED;

sliding a raised indexing feature of the nock body within a recessed indexing feature defined in the nock housing; and

preventing the nock body from rotating relative to the nock receiver while moving the nock body towards the nock receiver to turn on the LED and while moving the nock body away from the nock receiver to turn off the LED via the sliding of the raised indexing feature of the nock body within the recessed indexing feature defined in the nock housing.

14. The method of claim 13 , wherein the raised indexing feature of the nock body is an index tab and wherein the recessed indexing feature defined in the nock housing is an index slot.