Abstract: An infrared laser beam (B1) is irradiated from a transmitter (100) toward a window pane (410) of a building (400), and a reflected laser beam (B2) is received by a receiver (200). A laser spot (Q) picked up by a CCD camera is displayed on respective target display units (113, 213). Within the receiver, there are provided a photo-cell for outputting an electric signal corresponding to light energy of the reflected beam, and a knife edge for shielding a portion of the reflected beam. Vibrational component of the window pane caused by voice in the room is detected as a positional change of the reflected beam. In determining an installation place of the receiver, a beam detector (300) comprised of a large number of light receiving elements is used to detect the reflected beam. The transmitter scans an object with the laser beam (B1) modulated by an audible frequency so that the reflected beam (B2) is easily detected.

Abstract: A flashlight with signaling lamp suitable for miniaturization and having good operability is provided. A cylindrical slide body (20) is fitted over the outside of the upper portion of the main body (10) within which a battery is accommodated. When the slide body (20) is slid in upper and lower directions of the figure, the entirety thereof is expanded or contracted. A colorless transparent plate (24) and a reflection plate (25) are provided within an illuminating tubular portion (21). When the entirety is contracted, lamp bulb (40) is positioned within the illuminating tubular portion (21). Thus, this flashlight can be utilized as an illuminating lamp to irradiate the upper direction of the figure. In contrast, when the entirety is expanded, a scattered light by a signaling tubular portion (22) comprised of transparent plastic of red is obtained. Thus, this flashlight can be utilized as a signaling lamp. Inside the signaling tubular portion (22), a groove (22C) is dug.