Abstract:
PURPOSE: A measuring device for a standard penetration test using a laser is provided to easily measure the intrusion amount of a measuring rod using a laser. CONSTITUTION: A measuring device for a standard penetration test using a laser is composed as follows. A measuring rod(120) is installed in the inner center of a reinforcing pipe(110) buried in the ground, and is inserted into a borehole. A knocking head(130) is integrally installed in the top end of the measuring rod. A hitting amount measuring unit is integrally installed in one side of the knocking head. A hitting hammer(140) is located on the top of the knocking head. An intrusion amount measuring unit is installed in the measuring rod. An automatic recording unit(150) is connected to the measuring unit.
Abstract:
A diffraction grating (22) and a prism (26) with the appropriate characteristics are employed to provide a combined dispersive characteristic that is substantially linear over the visible spectrum. Radiation from the grating (22) and prism (26) is collimated by a lens (26b) towards a detector array (28). The grating (22) or a telecentric stop between the grating (22) and prism (26) is placed at a focal point of the lens (26b) in a telecentric arrangement so that equal magnification is achieved at the detector array (28). If the detector array (28) is replaced by a plurality of optical channels, a multiplexer/demultiplexer is obtained
Abstract:
Two or more triangular apertures are employed to pass radiation from a source to a detector to reduce the amount of stray radiation received by the detector. Preferably, the two apertures are equilateral triangels oriented at 60 DEG rotated relative to each other and have dimensions proportional to their distances from the sensor. A Bessel filter is employed to reduce the effect of flicker and other rapid changes in intensity in the radiance from the source. The output of the sensor is integrated and sampled at sampling time intervals that are powers of two of time, and a reading is provided when the output of the integrator exceeds the same threshold under all radiation source intensity conditions so that the meter has a substantially constant resolution at different signal levels.
Abstract:
A diffraction grating and a prism with the appropriate characteristics are employed to provide a combined dispersive characteristic that is substantially linear over the visible spectrum. Radiation from the grating and prism is collimated by a lens towards a detector array. The grating or a telecentric stop between the grating and prism is placed at a focal point of the lens in a telecentric arrangement so that equal magnification is achieved at the detector array. If the detector array is replaced by a plurality of optical channels, a multiplexer/demultiplexer is obtained.
Abstract:
Two or more triangular apertures are employed to pass radiation from a source to a detector to reduce the amount of stray radiation received by the detector. Preferably, the two apertures are equilateral triangles oriented at 60° rotated relative to each other and have dimensions proportional to their distances from the sensor. A Bessel filter is employed to reduce the effect of flicker and other rapid changes in intensity in the radiance from the source. The output of the sensor is integrated and sampled at sampling time intervals that are powers of two of time, and a reading is provided when the output of the integrator exceeds the same threshold under all radiation source intensity conditions so that the meter has a substantially constant resolution at different signal levels.