Thermal imaging device with selectively replaceable telescopic lenses and automatic lens identification

摘要

A thermal imaging device (10) provides for its use with a variety of accessory telescopic lenses (12). Each of the accessory telescopic lenses (12) and the thermal imaging device (10) include cooperating physical features allowing the lenses (12) to be mated with the device (10) in a single relative position. Each lens (12) also carries a uniquely positioned magnet (176), and the thermal imaging device (10) includes a plurality of magnetically-responsive sensors (178) responding to the magnets (176) of the various lenses (12) to identify which (if any) of the accessory lens (12) is installed on the device (10). Some of the accessory lenses (12) also include a variable-power feature. These variable-power lenses (12) have an additional magnet (182) moving between an effective position and an ineffective position in response to a user-selected power setting for the lens (12). The thermal imaging device (10) includes an additional magnetically-responsive sensor (178) affected by the additional magnet (182) in its effective position, but not effected in the ineffective position of this additional magnet (182). Thus, the thermal imaging device (10) also identifies the power setting of an installed variable-power lens (12). The thermal imaging device (10) is provided with internal adjustments and operational options which are automatically implemented dependent upon which of the accessory lenses (12) a user installs on the device (10).