California Polytechnic State University (Cal Poly) has an active photonics-related program. The thrusts of the program are coursework, extensive photonic educational laboratories, an SPIE student branch chapter, and a new Project-Based Learning Institute (PBLI) to promote joint projects with industry. This paper will describe our program for a multidisciplinary approach to photonics education at the undergraduate and master’s degree level.
We report using a fast-shuttering CCD camera to determine the transverse stiffness of an optical
tweezers trap. By utilizing the relation between the particle position variance and the trap
stiffness we are able to circumvent the sampling requirements of the position power spectrum
approach. We find that for trap stiffness of order 10-5 N/m exposures shorter than 0.001 sec seem
to be required in order to give valid measurements. For longer exposures (~0.01 sec) the trap
stiffness can be overestimated by a factor of three or more.
An optoelectronic system has been designed to pre-screen pap-smear slides and detect the suspicious cells using the hit/miss transform. Computer simulation of the algorithm tested on 184 pap-smear images detected 95% of the suspicious region as suspect while tagging just 5% of the normal regions as suspect. An optoelectronic implementation of the hit/miss transform using a 4f Vander-Lugt correlator architecture is proposed and demonstrated with experimental results.
In this paper we consider the formation of morphological templates using adaptive resonance theory. We examine the role of object variability and noise on the clustering of different sized objects as a function of the vigilance parameter. We demonstrate that the fuzzy adaptive resonance theory is robust in the presence of noise but that for poor choice of vigilance there is a proliferation of prototypical categories. We apply the technique to detection of abnormal cells in pap smears.
In this paper we describe our recent work developing automated methods for generation of kernels or structuring elements for use in the hit-or-miss transform. We show how a neural network algorithm (Fuzzy Adaptive Resonance Theory) generates hit and miss structuring elements that can be used with a fuzzy morphology to detect a class of objects and we illustrate with computer simulations.
Automation of the Pap-smear cervical screening method is highly desirable as it relieves tedium for the human operators, reduces cost and should increase accuracy and provide repeatability. We present here the design for a high-throughput optoelectronic system which forms the first stage of a two stage system to automate pap-smear screening. We use a mathematical morphological technique called the hit-or-miss transform to identify the suspicious areas on a pap-smear slide. This algorithm is implemented using a VanderLugt architecture and a time-sequential ANDing smart pixel array.
We present the design and test results of an optoelectronic feature detector array for use in a fingerprint ridge extraction system. The system comprises a microlens array for taking multiple Fourier transforms and an array of detectors. Each detector is composed of a set of wedge photodetectors with associated winner-take-all circuitry and encoders for reporting the maximally stimulated wedge element.