Abstract: A laser light receiver is provided with an integral laser distance measurement (LDM) device for measuring the distance from a laser plane of a desired elevation to a desired physical target point to be measured on a jobsite. The laser receiver can be combined with a gravity reference device, so that the laser receiver does not necessarily have to be held plumb to a desired target point, when determining the relative elevation of the laser receiver between a rotating beam of laser light and the target point; it can also acquire multiple samples of positions and automatically take a vertical measurement and store that result for later readout. The laser receiver can be further combined with a GPS receiver, to acquire latitude and longitude data, and then in combination act as a three-dimensional transducer that is more accurate in the vertical direction than a GPS receiver alone is capable of.

Abstract: A laser light receiver is provided with an integral laser distance measurement (LDM) device for measuring the distance from a laser plane of a desired elevation to a desired physical target point to be measured on a jobsite. The laser receiver can be combined with a gravity reference device, so that the laser receiver does not necessarily have to be held plumb to a desired target point, when determining the relative elevation of the laser receiver between a rotating beam of laser light and the target point; it can also acquire multiple samples of positions and automatically take a vertical measurement and store that result for later readout. The laser receiver can be further combined with a GPS receiver, to acquire latitude and longitude data, and then in combination act as a three-dimensional transducer that is more accurate in the vertical direction than a GPS receiver alone is capable of.

Abstract: A laser reference system orients a reference plane of laser light generated by a transmitter so compensation is made for a rake angle between the first and second axes of the transmitter and an alignment axis and an axis perpendicular thereto. The transmitter includes an optical system arranged to generate a laser beam, the optical system projecting said laser beam radially along a rotational arc defined about a central rotational axis, thereby substantially defining a reference plane of laser light, and a positioning arrangement, coupled to said optical system, for adjusting the angular orientation of the optical system with respect to a first transmitter axis and with respect to a second transmitter axis. A detector is arranged to detect reception of the laser beam. The detector includes a generally vertically arranged row of detector elements. The detector further includes a transmitter for transmitting information regarding the location of said laser beam, as detected by said detector elements.

Abstract: A laser reference system orients a reference plane of laser light generated by a transmitter so compensation is made for a rake angle between the first and second axes of the transmitter and an alignment axis and an axis perpendicular thereto. The transmitter includes an optical system arranged to generate a laser beam, the optical system projecting said laser beam radially along a rotational arc defined about a central rotational axis, thereby substantially defining a reference plane of laser light, and a positioning arrangement, coupled to said optical system, for adjusting the angular orientation of the optical system with respect to a first transmitter axis and with respect to a second transmitter axis. A detector is arranged to detect reception of the laser beam. The detector includes a generally vertically arranged row of detector elements. The detector further includes a transmitter for transmitting information regarding the location of said laser beam, as detected by said detector elements.

Abstract: A ply break detector for a laminate web uses a short time constant low pass filter and a long time constant low pass filter for filtering output signals from a sonic web scanner. A difference circuit compares output signals from the two filters to create a difference signal. A ply discontinuity indication is generated when the difference signal exceeds a predetermined threshhold with a predetermined persistence. Analog and digital versions are disclosed.

Abstract: Apparatus operable in accordance with the method of the present invention for measuring the angle of incidence of a light beam or plane relative to level comprises a photodetector array for sensing the light and a level mirror preferably comprising a pool of mercury. Optics are provided for transmitting the light to the photodetector array in alignment with the angle of incidence of the light (aligned light) and also after the light has been reflected from the mercury pool (reflected light). A shutter is provided for separating aligned light from reflected light such that distinct signals representative of the two are generated by the photodetector array. The distinct signals are processed by up-counting and down-counting a counter circuit to determine the average centers of light spots representative of the aligned light and the reflected light and the distance between those average centers which is representative of the deviation of the light beam or plane from level.