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A resonator fiber optic gyro (RFOG) based on a fiber-coupled semiconductor DFB-LD with an FPGA-based digital processor is set up. A bias stability of 23deg/h over one hour is successfully demonstrated. This is the best result in long time stability reported to date, to the best of our knowledge, for the RFOG based on a miniaturized laser source.

Experiments on resonator micro-optic gyro (RMOG) with a digital proportional integral (PI) feedback scheme are performed. In this experimental setup, the key rotation sensing element is a polarization maintaining silica waveguide ring resonator (WRR) with a ring length of 7.9 cm and a diameter of 2.5 cm. A good linearity of 0.0015% over a wide range of ± 2 × 10 4 °/s can be achieved for the RMOG theoretically. The optimal digital PI feedback scheme is adopted in the frequency servo loop to reduce the reciprocal frequency fluctuations due to the WRR resonance frequency and laser frequency drifts. Residual equivalent input fluctuation can be reduced as low as 0.03 °/s/√Hz based on the optimal digital PI feedback scheme, which is close to the shot noise limited spectral density 0.02 °/s/√Hz of the RMOG with the input optical power of 0.2 mW. Relationship between RMOG output signal and angular rate is obtained from ± 0.1 °/s to ± 5 °/s. The standard deviation of the residuals between RMOG output results and linear fit curve is 0.066 °/s. For an integration of the processing circuit, all the processing circuit is implemented by a field programmable gate array (FPGA) instead of instruments. The output of this digitalized RMOG is obtained over a range of ± 550 °/s. The linearity of this digitalized RMOG is 0.0169%.

After completing the development of a digital detector with a format of 640x512 elements ("Sebastian"), SCD is now developing a mid format digital detector with 480x384 elements. This detector is based on the same concept as Sebastian, which was introduced last year at the SPIE conference in Orlando. The 480x384 element detector has all the features and performance of Sebastian as then introduced, and in addition exhibits some additional functionality. The format of the 480x384 element detector was chosen in order to maintain the same active area as in a standard format 320x256 element detector of today. Thus with specific system optics, a higher resolution is achieved with our new detector. As a direct consequence, the detection range is increased by 22-35% depending on the target type, when using this detector instead of the conventional 320x256 element detector in a typical system. The 480x384 element detector is designed to be integrated both into imaging systems and into head seekers missile-applications. In this paper we present the concept and the basic structure of the detector, the special operation modes unique to the digital detector, and the results of detection range calculations.

This paper describes algorithmic development toward an automated process that generates a same patient sequence of fundic images that are normalized in position and intensity and have noise artifacts removed. Normalization of these fundic images is a key first step to further automatic analysis for the presence or progress of ophthalmic diseases. The Litton PRC team, inclusive of LItton Data Systems and Tomey Inc., evaluated the potential use of a hybrid optical/digital processor in the normalization of ophthalmic imagery. PRC provided the funding, initial architecture and approach for disease analysis using the optical processor. Tomey Inc. provided the fundus imagery and clinical advice on 'normalization' or images prior to undertaking the disease analysis. Litton Data Systems prototyped the algorithms and test using a rapid application prototyping tool for object recognition. The team approach was to do a coarse vessel alignment to bring the images within a to-be-determined level of alignment, and the repeat the algorithms at a threshold and alignment for fine vessels. The success of the coarse work encouraged the investigation of algorithms for processing higher resolution images with greater accuracy. The combined results completed the IRAD investigation and are shown as successfully aligning two images.

The mentality as a processing of information differ from known technical methods which have not possibility of a conception formation about unknown objects or an appearance perceived by sense organs using the standart base of individual. Process of a conception formation is begin with verbal enquiry (for example, ' 'House' ' ) after that the standarts (sign vectors) from according to class ' 'House' ' are compared with observed and transformed, analysed association.

Digital optical processors are designed to combine ultra- parallel data procesing capabilities of optical aystems cnd high accur&cy of performed computations. The ultimate limit of the processing rate can be anticipated from all-optical parcllel erchitecturea based on networks o logic gates using materials exibiting strong electronic nonlinearities with response times less than 1O seconds1.

A digital correlator/spectrum analyzer has been developed for the analysis of signals of 0-5 MHz bandwidth. The simple architecture includes two analog input channels (allowing crosscorrelation and cross-spectral analysis), 8-bit quantization, correlation calculation with up to 128 lags, and DFT output circuitry. Correlation functions and spectra are produced at intervals of 1 ms or longer, in both analog and digital form. Pipeline architecture allows unity duty cycle operation, with no loss of data between spectra. Extensive use of parallelism and LSI arithmetic units makes possible computing power of over 600 million operations per second in an 8" high package which requires about 200 watts.

In this paper, we present a new hybrid optical / digital processor that computes the geometric moments using the recently introduced Hartley transform (HT) . This transform has the attractive property of being real when the signal is real. We prove an important result that all geometric moments of an image can be computed recursively from the various partial derivatives (near origin) of the HT intensity .

Digital processing systems are examined for ECG and EEG signal analysis, in particular to perform filtering and spectral estimation operations. A new special digital processor is presented to perform multiple filterings and spectral estimations on several biomedical signals as ECG and EEG. Two implementation solutions are presented, having different structure and complexity. Experimental results obtained by using the digital processors for analysing EEG signals are shown for high efficiency filtering and spectral estimation. In particular the interest of using the processors to perform 2-D analysis on ECG-EEG signals is outlined.© (1982) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.