Range finder for automatically setting camera zoom magnification
The present invention relates to a range finder which measures a distance to a target after properly setting a zoom magnification of a camera to aim at the target in a captured preview image on the basis of a distance calculated using the GPS method of a combination of a global positioning system (GPS) method and a laser method.
1 . A range finder for automatically setting a camera zoom magnification, the range finder comprising:
an application processor;
a camera which captures an image of a target through one or more camera modules that include an image sensor, a zoom lens, and a lens barrel and provide an optical zoom function;
a global positioning system (GPS) receiver which receives GPS signals and extracts current location information;
a memory storing map data and program instructions,
wherein the application processor is configured to execute the program instructions to:
calculate a distance to the target using location information of the target on the stored map data and the current location information;
determine an optical zoom magnification of the camera module based on the calculated distance to the target and set a zoom magnification of the camera module; and
aim at the target in an image captured at the set zoom magnification and measure a distance to the target using a laser.
2 . The range finder of claim 1 , further comprising a display which displays a preview image captured by the camera at the set zoom magnification.
3 . The range finder of claim 2 , wherein the display displays the preview image on an entire display region and displays a map image, which is related to the current location information, to be overlaid with the preview image at one side of the display region.
4 . The range finder of claim 1 , wherein:
the camera provides a digital zoom function; and
the application processor sets a zoom by combining an optical zoom magnification and a digital zoom magnification.
5 . The range finder of claim 1 , wherein the application processor is further configured to execute program instructions to recognize the target from a preview image captured by the camera at the set zoom magnification.
6 . The range finder of claim 5 , wherein the application processor is configured to automatically measure the distance to the target when the target is recognized from the preview image.
7 . A method of measuring a distance by automatically setting a camera zoom magnification, which is performed by a range finder, the method comprising:
a global positioning system (GPS) reception operation of receiving GPS signals and extracting current location information
a distance calculating operation of calculating a distance to a target using location information of the target on stored map data and the current location information;
a zoom setting operation of determining and setting an optical zoom magnification of a camera module on the basis of the calculated distance to the target and setting a zoom magnification of the camera module;
a target image capturing operation of capturing an image of the target using one or more camera modules at the automatically set optical zoom magnification; and
a distance measuring operation of measuring a distance to the target using a laser.
8 . The method of claim 7 , further comprising a display operation of displaying a preview image captured by the camera module at the set zoom magnification.
9 . The method of claim 8 , wherein the display operation includes displaying the preview image on an entire display region and displaying a map image, which is related to the current location information, to be overlaid with the preview image at one side of the display.
10 . The method of claim 7 , wherein the zoom setting operation includes setting a zoom by combining the optical zoom magnification and a digital zoom magnification.
11 . The method of claim 7 , further comprising a target recognizing operation of recognizing the target from a preview image captured by the camera module at the set zoom magnification.