A method of detecting a substance includes, for each position of a plurality of positions in a field of view of an environment: emitting from a light source a light beam including a predetermined wavelength that is absorbable by a constituent of the substance, controlling at least one mirror to direct the emitted light beam to the position in the field of view, detecting by a detector light resulting from the emitted light beam, and determining whether the constituent of the substance is present at the position in the field of view based on characteristics of the detected light; generating a detection map indicating a presence or an absence of the substance at the plurality of positions in the field of view of the environment; capturing, by an image capture device, an image of the environment; and identifying a portion of the captured image having the substance based on the detection map.

One aspect of the invention relates to a method of detecting a spatial orientation of a transducer by a handheld optical scanning device. The method comprises steps of providing a first spatial orientation feature on at least a first outer housing surface of the transducer and arranging a handheld optical scanning device in a sightline of the first spatial orientation feature at a selected spatial orientation relative to the first outer surface of the transducer housing. The method comprises further steps of identifying the first spatial orientation feature, detecting a spatial orientation of the handheld scanning device in a predetermined coordinate reference system and determining a spatial orientation of the transducer in the predetermined coordinate reference system.

According to one embodiment of the present invention, a terahertz wave concentrating module can comprise: a first lens for changing a terahertz wave, which is emitted while a terahertz Bessel beam penetrates an object to be inspected, so as to have a small angle; and a second lens for concentrating, on a detector, the terahertz wave having passed through the first lens.

According to one embodiment of the present invention, a terahertz wave concentrating module can comprise: a first lens for changing a terahertz wave, which is emitted while a terahertz Bessel beam penetrates an object to be inspected, so as to have a small angle; and a second lens for concentrating, on a detector, the terahertz wave having passed through the first lens.

An optoelectronic sensor (10) is provided for detecting transparent objects (30) in a monitored zone (22) that has a light transmitter (12) for transmitting a light signal (14), a light receiver (26) for generating a received signal from the received light signal, an evaluation unit (28) that is configured to evaluate the received signal and to generate an object determination signal that indicates whether a transparent object (30) has been detected in the monitored zone (22), and an output (32) for outputting the object determination signal. The evaluation unit (28) is further configured to recognize with respect to the received signal and to a piece of reference information whether a detected transparent object (30) has an additional feature (34) and to output a corresponding piece of additional feature information.

An optoelectronic sensor (10) is provided for detecting transparent objects (30) in a monitored zone (22) that has a light transmitter (12) for transmitting a light signal (14), a light receiver (26) for generating a received signal from the received light signal, an evaluation unit (28) that is configured to evaluate the received signal and to generate an object determination signal that indicates whether a transparent object (30) has been detected in the monitored zone (22), and an output (32) for outputting the object determination signal. The evaluation unit (28) is further configured to recognize with respect to the received signal and to a piece of reference information whether a detected transparent object (30) has an additional feature (34) and to output a corresponding piece of additional feature information.

A high resolution inspection apparatus using a terahertz Bessel beam. The high resolution inspection apparatus comprises a terahertz wave generating unit for generating a terahertz wave; a Bessel beam forming unit for forming a terahertz Bessel beam at an inspection target object using a terahertz wave incident from the terahertz wave generating unit; a first lens for changing an angle of the terahertz wave radiated, when the terahertz Bessel beam is transmitted through the inspection target object, to be smaller; a second lens for concentrating the terahertz wave passing through the first lens and toward a detection unit; and a terahertz wave detection unit for detecting the terahertz wave concentrated by the second lens.

A high resolution inspection apparatus using a terahertz Bessel beam. The high resolution inspection apparatus comprises a terahertz wave generating unit for generating a terahertz wave; a Bessel beam forming unit for forming a terahertz Bessel beam at an inspection target object using a terahertz wave incident from the terahertz wave generating unit; a first lens for changing an angle of the terahertz wave radiated, when the terahertz Bessel beam is transmitted through the inspection target object, to be smaller; a second lens for concentrating the terahertz wave passing through the first lens and toward a detection unit; and a terahertz wave detection unit for detecting the terahertz wave concentrated by the second lens.

According to one embodiment of the present invention, a terahertz wave concentrating module can comprise: a first lens for changing a terahertz wave, which is emitted while a terahertz Bessel beam penetrates an object to be inspected, so as to have a small angle; and a second lens for concentrating, on a detector, the terahertz wave having passed through the first lens.

According to one embodiment of the present invention, a terahertz wave concentrating module can comprise: a first lens for changing a terahertz wave, which is emitted while a terahertz Bessel beam penetrates an object to be inspected, so as to have a small angle; and a second lens for concentrating, on a detector, the terahertz wave having passed through the first lens.