Abstract: An optical magnetometer is disclosed. The device includes a cell filled with a substance that has a magnetic moment, such as an alkali metal. First and second light sources, typically diode lasers, illuminate the cell, one optically pumping the cell and one probing the cell. The two diode lasers are set to emit light at two distinct wavelengths, one set to drive a first transition and the other set to drive a second transition within the substance filling the cell. The probe laser light transiting the cell is used to modulate the frequency of the probe laser. The two beams of light are polarized with an ellipticity of at least 0.3.

Abstract: A quantum mechanical measurement device is provided. A spin ensemble is provided. A first light source provides a first light at a first wavelength, wherein the first light source is positioned to provide light into the spin ensemble. A detector is positioned to detect light from the spin ensemble. A modulator modulates absorption of the first light from the first light source by the spin ensemble at a frequency greater than a Larmor frequency of the spin ensemble.

Abstract: In a first embodiment of the present invention, a hydrophone is provided comprising: a rigid tubular substrate; an annular cavity formed around the rigid tubular substrate by affixing a tubular diaphragm around the rigid tubular substrate; a flexible piezoelectric element wrapped around and bonded to the flexible tubular diaphragm; and a molded portion covering the piezoelectric element.

Abstract: A quantum mechanical measurement device is provided. A spin ensemble is provided. A first light source provides a first light at a first wavelength, wherein the first light source is positioned to provide light into the spin ensemble. A detector is positioned to detect light from the spin ensemble. A modulator modulates absorption of the first light from the first light source by the spin ensemble at a frequency greater than a Larmor frequency of the spin ensemble.

Abstract: In a first embodiment of the present invention, a hydrophone is provided comprising: a rigid tubular substrate; an annular cavity formed around the rigid tubular substrate by affixing a tubular diaphragm around the rigid tubular substrate; a flexible piezoelectric element wrapped around and bonded to the flexible tubular diaphragm; and a molded portion covering the piezoelectric element.

Abstract: A magnetometer is constructed wherein the sweeping is performed at one half the Larmor frequency and has as its center the absorption line. This allows the emitter to tune onto the absorption line twice per cycle as it passes through the line. This causes the increase in absorption as would the normal sweep of a Bell-Bloom magnetometer but avoids the drawbacks, such as drift and heading error.

Abstract: A magnetometer is constructed wherein the sweeping is performed at one half the Larmor frequency and has as its center the absorption line. This allows the emitter to tune onto the absorption line twice per cycle as it passes through the line. This causes the increase in absorption as would the normal sweep of a Bell-Bloom magnetometer but avoids the drawbacks, such as drift and heading error.

Abstract: In an underground object locating system in which a modulated RF signal is applied to the underground object and an emitted signal is detected by a receiver, ambiguity in the direction of current flow in the underground object is resolved by modulating the RF signal with a modulation signal such that the modulated signal, f(t) has an average value of zero and is not equal to ?f(t+K) where K is any practical value. In specific embodiments, the modulation can be amplitude modulation where the modulating signal is lower in frequency than the RF signal and is related thereto by a rational number, such as one-half (½).

Abstract: In an underground object locating system in which a modulated RF signal is applied to the underground object and an emitted signal is detected by a receiver, ambiguity in the direction of current flow in the underground object is resolved by modulating the RF signal with a modulation signal such that the modulated signal, f(t) has an average value of zero and is not equal to −f(t+K) where K is any practical value. In specific embodiments, the modulation can be amplitude modulation where the modulating signal is lower in frequency than the RF signal and is related thereto by a rational number, such as one-half (½).

Abstract: A reflection seismograph collects data received over a plurality of channels in a field location and provides data recorded on a recording medium for processing at a home data processing site in accordance with well-known algorithms. Data is collected over a plurality of channels and converted into a recordable form. In accordance with the present invention, the data is not coupled directly to recording means but is stored. Stored data is processed by a post acquisition processor so that a field operator may preview data to make a determination as to whether the data inputs are suitable to provide a desired result when processed at the home location. The operation may then actuate a means for recording the data onto the recording medium.

Abstract: In a system for providing maximum display deflection within a preselected scale size for a time-varying imput whose envelope may be monotonically decreasing, or otherwise varying, automatic gain control means produces a multiplication factor by which an input signal is multiplied to provide an output signal for provision to utilization means such as a display. The multiplier signal is produced as a function of an error signal. The output signal is compared to a value indicative of a desired trace size to produce a signal representative of percentage error rather than a difference. The percentage error is subtracted from 100% to provide a gain error signal, a function of which is the multiplier signal. The function may be further generated by sampling the gain error signal over a window length and summing the samples. The integral thus obtained may be utilized as an exponent in the value of the multiplication factor.

Abstract: In a floating point digitizer, an analog signal is delivered to two signal paths. One includes a delay line. In the first path, the analog signal is measured in terms of order of magnitude to provide a signal indicative of an exponent. This same value is utilized to set the gain of a variable gain amplifier to which the delayed signal is applied and from which a mantissa is resolved.