Nisan Ozana

Improved noncontact optical sensor for detection of glucose concentration and indication of dehydration level

The ability to extract different bio-medical parameters from one single wristwatch device can be very applicable. The wearable device that is presented in this paper is based on two optical approaches. The first is the extraction and separation of remote vibration sources and the second is the rotation of linearly polarized light by certain materials exposed to magnetic fields. The technique is based on tracking of temporal changes of reflected secondary speckles produced in the wrist when being illuminated by a laser beam. Change in skins temporal vibration profile together with change in the magnetic medium that is generated by time varied glucose concentration caused these temporal changes. In this paper we present experimental tests which are the first step towards an in vivo noncontact device for detection of glucose concentration in blood. The paper also shows very preliminary results for qualitative capability for indication of dehydration.

Demonstration of a Remote Optical Measurement Configuration That Correlates With Breathing, Heart Rate, Pulse Pressure, Blood Coagulation, and Blood Oxygenation

An optical approach to the extraction and separation of remote vibration sources has recently been proposed. The technique has previously been applied successfully to biomedical measurements including pulse pressure, heart rate, blood glucose and alcohol concentrations, and intraocular pressure. In this paper, we review this optical sensing technology and demonstrate its ability to monitor three additional biomedical indicators, breathing, blood oximetry, and blood coagulation, as well as its ability to simultaneously monitor indicators that were previously only monitored separately. The proposed compact and potentially low-cost biomedical sensor can be highly beneficial given the global healthcare challenges, especially in the developing countries.

Noncontact optical sensor for bone fracture diagnostics

We present the first steps of a device suitable for detection of broken and cracked bones. The approach is based on temporal tracking of back reflected secondary speckle patterns generated when illuminating the limb with a laser and while applying periodic pressure stimulation via a loud speaker. Preliminary experiments are included showing the validity of the proposed device for detection of damaged bones.

Noncontact speckle-based optical sensor for detection of glucose concentration using magneto-optic effect

Abstract. We experimentally verify a speckle-based technique for noncontact measurement of glucose concentration in the bloodstream. The final device is intended to be a single wristwatch-style device containing a laser, a camera, and an alternating current (ac) electromagnet generated by a solenoid. The experiments presented are performed in vitro as proof of the concept. When a glucose substance is inserted into a solenoid generating an ac magnetic field, it exhibits Faraday rotation, which affects the temporal changes of the secondary speckle pattern distributions. The temporal frequency resulting from the ac magnetic field was found to have a lock-in amplification role, which increased the observability of the relatively small magneto-optic effect. Experimental results to support the proposed concept are presented.

Remote optical configuration of pigmented lesion detection and diagnosis of bone fractures

In this paper we present a novel approach of realizing a safe, simple, and inexpensive sensor applicable to bone fractures and pigmented lesions detection. The approach is based on temporal tracking of back-reflected secondary speckle pattern generated while illuminating the affected area with a laser and applying periodic pressure to the surface via a controlled vibration. The use of such a concept was already demonstrated for non-contact monitoring of various bio-medical parameters such as heart rate, blood pulse pressure, concentration of alcohol and glucose in the blood stream and intraocular pressure. The presented technique is a safe and effective method of detecting bone fractures in populations at risk. When applied to pigmented lesions, the technique is superior to visual examination in avoiding many false positives and resultant unnecessary biopsies. Applying a series of different vibration frequencies at the examined tissue and analyzing the 2-D speckle pattern trajectory in response to the applied periodic pressure creates a unique signature for each and different pigmented lesion. Analyzing these signatures is the first step toward detection of malignant melanoma. In this paper we present preliminary experiments that show the validity of the developed sensor for both applications: the detection of damaged bones as well as the classification of pigmented lesions.

Optical remote sensor for peanut kernel abortion classification.

In this paper, we propose a simple, inexpensive optical device for remote measurement of various agricultural parameters. The sensor is based on temporal tracking of backreflected secondary speckle patterns generated when illuminating a plant with a laser and while applying periodic acoustic-based pressure stimulation. By analyzing different parameters using a support-vector-machine-based algorithm, peanut kernel abortion can be detected remotely. This paper presents experimental tests which are the first step toward an implementation of a noncontact device for the detection of agricultural parameters such as kernel abortion.

Remote optical sensor of blood coagulation, oximetry and dehydration

An optical approach for remote extraction of vibrations has recently been proposed. We demonstrate the methods ability to continuously monitor three biomedical indicators: blood oximetry, blood coagulation and dehydration of the body.

Demonstration of a Speckle Based Sensing with Pulse-Doppler Radar for Vibration Detection

In previous works, an optical technique for extraction and separation of remote static vibrations has been demonstrated. In this paper, we will describe an approach in which RF speckle movement is used to extract remote vibrations of a static target. The use of conventional radar Doppler methods is not suitable for detecting vibrations of static targets. In addition, the speckle method has an important advantage, in that it is able to detect vibrations at far greater distances than what is normally detected in classical optical methods. The experiment described in this paper was done using a motorized vehicle, which engine was turned on and off. The results showed that the system was able to distinguish between the different engine states, and in addition, was able to determine the vibration frequency of the engine. The first step towards real time detection of human vital signs using RF speckle patterns is presented.

Remote optical stethoscope and optomyography sensing device

In this paper we present the usage of photonic remote laser based device for sensing nano-vibrations for detection of muscle contraction and fatigue, eye movements and in-vivo estimation of glucose concentration. The same concept is also used to realize a remote optical stethoscope. The advantage of doing the measurements from a distance is in preventing passage of infections as in the case of optical stethoscope or in the capability to monitor e.g. sleep quality without disturbing the patient. The remote monitoring of glucose concentration in the blood stream and the capability to perform opto-myography for the Messer muscles (chewing) is very useful for nutrition and weight control. The optical configuration for sensing the nano-vibrations is based upon analyzing the statistics of the secondary speckle patterns reflected from various tissues along the body of the subjects. Experimental results present the preliminary capability of the proposed configuration for the above mentioned applications.

Nanostructures with periodic heating–cooling cycles for photoacoustic imaging using continuous-wave illumination

Abstract. Over the last few years, there is a growing interest in photoacoustic imaging using nanoparticles techniques due to the improved penetration depth and resolution. Working with such nanoparticles usually requires pulsed laser illumination to generate an acoustic signal in the right frequencies. However, these pulsed lasers are considered expensive and complicated with respect to continuous-wave (CW) illumination. We design and simulate a special nanostructure with overall dimensions of 190×50× (26–34) nm, which blinks with fast temporal periodicity of 20 to 40 ns, under CW illumination and can be used for the generation of acoustic signals. This blinking is done using the enhanced optical absorption of metallic nanoparticles due to localized surface plasmon resonance (SPR) and the thermal expansion to generate heating–cooling cycles of the nanostructure. The CW laser wavelength is adapted to the localized SPR of the metallic nanostructure at the NIR region, which provides maximum penetration depth of light into biological tissues.