A diagnostic monitor for classifying biological tissue in which a light emitter (102) is optically coupled to the tissue to be diagnosed (145) and a light detector (174) is optically coupled to the tissue to detect a portion of the light which passes through the tissue. The tissue classifier (184) receives a signal from the detector and provides an optical classification output signal (195), wherein the tissue is classified by type or state, either for detection, localization, or imaging. A method of classifying tissue is also described.

Device and method for classification of tissue

A distance measuring method and apparatus in which first and second pseudo random signals which are the same in pattern but slightly different in period are generated to obtain a correlation output of the first and second pseudo random signals before transmission thereof as a reference correlation output, and the first pseudo random signal is directly transmitted toward a target or alternatively a carrier wave is modulated by the first pseudo random signal and transmitted toward the target. A correlation output of the signal reflected and received from the target and the second pseudo random signal is detected and the distance to the target is measured from the time interval between the reference correlation output and the received correlation output. Alternatively, the modulated carrier wave reflected and received from the target and the second pseudo random signal are subjected to correlation processing to detect a correlative modulated carrier wave and the correlative modulated carrier is subjected to orthogonal detection by a reference carrier wave thereby obtaining a target detection output. Then, the distance to the target is measured from the time interval between the reference correlation output and the target detection output.

Distance measuring method and apparatus therefor

A device and method of electronically obtaining range or distances from the device to the target utilizing a central processing unit (CPU) in combination with a pulse repetition frequency generator, a plurality of photodetectors and a transistor to transistor clock counter, in a lightweight and portable configuration. The device obtains a plurality of samples, which enables the CPU to determine filter delay, range resolution and count deviations so as to accurately determine range or distance measurement to within plus or minus one centimeter.

Device and method for electronically measuring distances

An energy pulse capture system senses, receives, and processes signals reflected from a target. In an illustrative embodiment, light pulses are reflected off of a target, received by optical equipment, converted into analog electrical signals, and then processed to obtain information therefrom. The invention basically identifies targets by measuring the time delay between a transmitted signal and a received or "return" signal. The invention includes a windowing system to more efficiently process digitized electrical signals representing the return signals. The windowing system effectively defines a "window" in memory within which the return signal is stored, and "locks" on to this window to reduce time spent searching for the return pulses among other data. In another aspect of the invention, a real time return system is used to more efficiently process the electrical signals representing the return pulses. The real time return system detects the maximum amplitude of the received signal in real time, and stores the current value of a counter used to clock data into memory, thereby facilitating later use of the stored counter value to locate signals representative of the return signal in the memory. The invention also concerns a timing delay system, which conserves memory of the invention by delaying storage of data until a return pulse is actually received.

System for processing reflected energy signals

In an apparatus using an intensity-modulated light for detection of spatial information based upon light intensity of light reflected from a target space, a timing synchronization circuit is provided to synchronize a phase of the intensity-modulated light from a light-emitting element with a timing of operating a light-receiving element receiving the intensity-modulated light. The light-receiving element is caused to operate for enabling the detection of intensity of the received light for each of a plurality of phase regions within one cycle of the intensity-modulated light. The timing synchronization circuit functions to compare a cyclic variation determining the operation of the light-receiving element with a cyclic variation associated with an output from a light-emitting element driving circuit in order to keep a constant phase difference between these two cyclic variations.

Spatial information detecting apparatus

A method and device are provided for measuring the propagation time of a wave, wherein a wave is transmitted modulated in amplitude by a modulation signal. The wave reflected by an obstacle is received after a propagation time and the amplitude thereof is detected. The average value of the product of the detected signal and a reference signal is calculated and the delay with respect to the modulation signal is controlled so as to cancel out the average value. The modulation signal and the reference signal comprise a succession of elementary signals chosen so as to allow, in a single measurement, a long propagation time to be determined without ambiguity and with high accuracy.

Method and device for measuring the propagation of a wave

On emet l'onde modulee en amplitude par un signal de modulation (S E ). On recoit l'onde reflechie par un obstacle apres un temps de propagation (τ t ) et on en detecte l'amplitude. On calcule la fonction d'intercorrelation entre le signal detecte (S R ) et un signal de reference (S Ral ) et on commande le retard ( T ) par rapport au signal de modulation (Se) pour annuler la fonction d'intercorrelation. Le signal de modulation (S E ) et le signal de reference (S pal ) comprennent une suite de signaux elementaires choisis pour permettre en une seule mesure, la determination d'un temps de propagation ( T ,) long sans ambiguite et avec une grande precision. L'invention s'applique, par exemple, a des dispositifs de mesure altimetriques a faisceau laser.

Michel Torregrosa

Papers

Method and device for measuring the propagation of a wave

Procédé et dispositif pour la mesure du temps de propagation d'une onde