Martin B. van der Mark

• PhD
• Principal Investigator at Philips

A standing wave of light inside a cavity, while observed from a moving frame, is seen to have a spatial beat of precisely the same nature as that of the de Broglie wave of a quantum particle. The structural forces that hold together the cavity against the internal radiation pressure are compared to the so-called Poincaré stresses inside an elementa...

Smart minimally invasive devices face a connectivity challenge. An example is found in intracardiac echocardiography where the signal transmission and supply of power at the distal end require many thin and fragile wires in order to keep the catheter slim and flexible. We have built a fully functional bench-top prototype to demonstrate that electri...

Platform: What physical attributes separate EM waves, of the enormous band of radio to visible to x-ray, from the high energy narrow band of gamma-ray? From radio to visible to x-ray, telescopes are designed based upon the optical imaging theory; which is an extension of the Huygens-Fresnel diffraction integral. Do we understand the physical proper...

Einstein's relativity theory appears to be very accurate, but at times equally puzzling. On the one hand, electromagnetic radiation must have zero rest mass in order to propagate at the speed of light, but on the other hand, since it definitely carries momentum and energy, it has non-zero inertial mass. Hence, by the principle of equivalence, it mu...

From super clusters of galaxies down to the quarks in the proton, at all length scales the structure of matter is the result of a balance of forces. In this paper it is argued that with decreasing size there must necessarily be an increase of the fraction of kinetic and binding energy with respect to the total energy. Smaller sizes require stronger...

Starting from a complex 4-potential A = αdβ we show that the 4-current density in electromagnetism and the probability current density in relativistic quantum mechanics are of identical form. With the Dirac-Clifford algebra Cl(1,3) as mathematical basis, the given 4-potential allows topological solutions of the fields, quite similar to Bateman's co...

Diagnostic value of minimally invasive medical devices can be improved by putting electronic functionality at the tip. At the same time the device should remain slim, flexible and affordable. We show transfer of high power and data over a catheter by a single optical fiber and LED. We find that simultaneous photovoltaic power conversion and data co...

A biopsy device is provided comprising a tubular member, a hollow shaft and an elongated fiber body. The hollow shaft may have a distal end and a shaft, wherein a laterally (sidewardly) facing notch is formed in the distal portion of the shaft. The elongated fiber body may include at least one optical fiber, preferably at least two optical fibers,...

Light from a super continuum source is dispersed into a number of wavelength bands, coded using a spatial light modulator and recombined into an optical fiber that delivers it to living tissue. Diffuse light emanating from the tissue is detected efficiently using an array of high numerical aperture, single-element photo detectors and spectrally res...

We show that the Lorentz force law, F^L_1=q_1(E+v_1xB) being the charge on particle 1 interacting with the electromagnetic fields due to all other particles, can be written in a pure field form F^L_1=-\nabla_1 U^{EM}. In this expression U^{EM} is the total electromagnetic energy of the system of particle 1 and all other particles. In deriving this...

Using scatterplots of 2 or 3 parameters, diffuse optical tomography and fluorescence imaging are combined to improve detectability of breast lesions. Small or low contrast phantom-lesions that were missed in the optical and fluorescence images were detected in the scatterplots. In patient measurements, all tumors were visible and easily differentia...

Light from a super-continuum source is spectrally dispersed, coded and recombined before illuminating a turbid medium. In this way, spectroscopic diffuse optical imaging of the medium of very high light collection efficiency is possible.

Waaruit bestaat alles? Wat is materie? Ooit dacht men dat er 4 basis elementen waren: aarde, lucht, water en vuur. Nu denken we dat er 4 basis krachten bestaan die de structuur bepalen van de kleinste afmeting van elementaire deeltjes tot op de grootste schaal van het universum zelf. Het huidige begrip is groot, indrukwekkend zelfs, maar er zijn oo...

A laser speckle contrast imaging (LSI) setup has been designed and used to estimate heartbeat rate and microvascular perfusion non‐invasively. LSI measurements were performed on the human index finger and thumb during various finger perfusion conditions, such as before and after gently rubbing of a finger or the healing of a small inflammation of t...

We demonstrate a method to estimate the concentrations of water and lipid in scattering media such as biological tissues with diffuse optical spectra acquired over the range of 900 to 1600 nm. Estimations were performed by fitting the spectra to a model of light propagation in scattering media derived from diffusion theory. To validate the method,...

We present the first clinical results of a novel fully automated 3D breast ultrasound system. This system was designed to match a Philips diffuse optical mammography system to enable straightforward coregistration of optical and ultrasound images. During a measurement, three 3D transducers scan the breast at 4 different views. The resulting 12 data...

This is the first clinical evaluation of a novel fluorescent imaging agent (Omocianine) for breast cancer detection with diffuse optical tomography (DOT). Eleven women suspected of breast cancer were imaged with DOT at multiple time points (up to 24 h) after receiving an intravenous injection of Omocianine (doses 0.01 to 0.1 mg/kg bodyweight). Brea...

We present a method to enhance tumor detectability in breasts imaged with our optical fluorescence mammography system. During a measurement, transmission data at 4 wavelengths and fluorescence data for excitation at 1 wavelength are collected after injection of an optical contrast agent. The data are reconstructed into 3D images of the absorption a...

This paper presents an evaluation of a prototype diffuse optical tomography (DOT) system. Seventeen women with 18 breast lesions (10 invasive carcinomas, 2 fibroadenomas, and 6 benign cysts; diameters 13-54 mm) were evaluated with DOT and magnetic resonance imaging (MRI). A substantial fraction of the original 36 recruited patients could not be exa...

The purpose of this study was to validate a newly developed diffuse optical tomography (DOT) system on benign cysts in the breast. Eight patients with 20 benign cysts were included. Study procedures consisted of optical breast imaging and breast magnetic resonance imaging (MRI) for comparison. A reconstruction algorithm computed three-dimensional i...

We describe a diffuse optical tomography system having both spectroscopic and fluorescence imaging capability. Some test results obtained in phantoms studies as well as our initial experience in patients are discussed.

This paper discusses our diffuse optical tomography system, the proof-of-principle results obtained in phantoms studies, our initial experience in patients and the impact on the breast cancer care cycle.

In this study, cystic breast lesions were imaged by spectral diffuse optical tomography. Spectroscopic analysis of the lesions elucidated their high water content and low total hemoglobin content. Article not available.

Diffuse optical tomography is a non-invasive method aiming at the detection of breast cancer. The sensitivity and specificity of the method can be increased if a fluorescent contrast agent is used that accumulates in malignant lesions. Recently, Philips developed an optical scanner, where the patient is lying on a bed, with one breast hanging freel...

We report on the first results obtained with the Philips diffuse optical tomography system and Schering AG's Omocianine fluorescent dye.

In this study, we present reconstruction results for optical tomography based on measurements with a 3D scanner using a finite element forward model. We show the importance of taking the correct Green's function everywhere, which is possible using the FEM approach. Further, it is shown that for the simple case of a few spheres in a homogeneous liqu...

We present the status of our efforts to demonstrate the feasibility of recording on a cover-layer protected dual-layer optical disc with a blue laser and NA=1.45 objective lens that is based on a solid immersion lens (SIL). We discuss the potential data density and some practical and theoretical considerations for the light path, the objective lens...

We present a single-wavelength near field recording set-up with a blue laser and a NA=1.9 solid immersion lens in a conventional focus and tracking actuator. The most important aspects to realize such a near field recording system are discussed, in particular, gap error signal normalization and correction of chromatic aberration of the objective le...

This paper describes development of a bi-axial actuator-based air gap servo system for a near field optical recording system using a blue laser and a solid immersion lens (SIL). We first present a new pull-in procedure ensuring smooth air gap servo start-up without lens-disc collision. Furthermore, a memory-loop control technique has been employed...

We present a near-field optical recording system with a solid immersion lens (SIL) in a conventional biaxial actuator. We manufactured a super-hemispherical aplanatic SIL with a numerical aperture (NA) of NA = 1.9. Our system utilizes a gap error signal (GES) and a digital servo system to drive a conventional actuator in order to maintain a constan...

We present read-out results of a 50 GB disk with a blue laser and a NA=1.9 Solid Immersion Lens in a conventional focus and tracking actuator. Furthermore, we show a light path and a disk design that enable cover-layer incident near field recording on dual-layer disks with a capacity of 300 GB on a double-sided disk.

A 10 micron free working distance recording head for blue, cover-layer incident MO recording has been developed with NA=0.95 and integrated high bandwidth MFM coil. ZF-MAMMOS recording experiments are described.

Recently, M. Sekine et al. (Techn. Digest ODS, pp 61, 2001) showed the first experimental results on a new MAMMOS magneto optical super resolution media type, which they call zero-field MAMMOS, that in contrast to the earlier developed AC MAMMOS type can be read-out without the need for any external modulating expansion field. These media were desi...

Einstein's relativity theory appears to be very accurate, but at times equally puzzling. On the one hand, electromagnetic radiation must have zero rest mass in order to propagate at the speed of light, but on the other hand, since it definitely carries momentum and energy, it has non-zero inertial mass. Hence, by the principle of equivalence, it mu...

© 2000 Optical Society of America

We show that the leakage current through a metal–semiconductor–metal photodetector can be reduced by placing a thin interfacial silicon dioxide layer between the Schottky metal and the silicon substrate. We measure a factor 5.2 reduction in leakage-current density to 18 μA/cm2 at 5 V, a weaker increase in dark current with bias, and a factor 3.5 im...

The results of the first set of clinical trials with the Philips optical mammography prototype system are summarized. This optical mammo prototype is designed to image the interior of the female breast with the help of near-infrared (NIR) laser light transmission measurements. This study is expected to lead to optical tomography systems for breast...

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Due to its nonionizing nature, optical mammography could be a very attractive alternative to X-ray screening. The authors have developed a cw optical tomography apparatus with which three-dimensional images of breasts can be obtained in vivo, and it is now being used for clinical research in the Academic Hospital in Maastricht. It measures the atte...

Due to its non-ionizing nature, optical mammography could be a very attractive alternative to X-ray screening. We have developed a CW optical tomography apparatus with which three-dimensional images of breasts can be obtained in vivo. It measures the attenuation coefficient κ =3 μ a μ s ' of the breast tissue. The magnitude of the reduced scatterin...

The Philips Optical Mammoscope Prototype is a versatile CW optical mammography apparatus with which fully 3D images of breast tissue can be obtained at several wavelengths. We present the properties of the machine, and show the first images obtained with it. We elaborate on the tissue parameter that can be quantitatively reconstructed from the meas...

Measurements and Monte Carlo simulations of the angular distribution of light scattered from wedge-shaped Polymer-Dispersed Liquid Crystals (PDLCs) are reported. The simulation model is based on two length scales: the scattering mean free path and the transport mean free path. The simulation reproduces the experimental angular distribution of multi...

Light scattering from polymer dispersed liquid crystal (PDLC) material has been studied experimentally and by Monte Carlo simulation. Light scattering was measured as a function of both scattering angle and cell thickness. The cell thicknesses of practical interest are in an intermediate regime where neither single scattering nor light diffusion ap...

We study the properties of a simple semi-classical model of a photon confned in periodic boundary conditions of one wavelength. The topology of this object, together with the photon electric field, give rise to a charge of the order of 10^-19 Coulomb and a half-integral spin, independent of its size. The ratio of the electromagnetic energy inside a...

The recent developments in light generation and detection techniques have opened new possibilities for optical medical imaging, tomography, and diagnosis at tissue penetration depths of ∼10 cm. However, because light scattering and diffusion in biological tissue are rather strong, the reconstruction of object images from optical projections needs s...

A modified backprojection image reconstruction method including corrections for blurring and refraction is described for medical optical tomography. This method is illustrated using cylindrical phantoms containing simple objects.

A modified backprojection image reconstruction method has been applied to obtain three dimensional (3D) experimental tomographic images of objects in biological-tissue-like diffusive media.

We describe a simple reconstruction method for diffuse optical imaging based on modified back-projection approach for medical tomography. These modifications are based primarily on the deconvolution of the broadened image by a point spread function which is dependent on the scattering of light in tissue. The nonlinearities in the image formation ar...

A new, contactless and nondestructive method for measuring the diameter of an optical fiber is described which has 10 nm sensitivity. In this method, polarized laser light is backscattered from the fiber, perpendicular to its axis. The measured intensity shows excellent agreement with calculations from an exact scattering theory, and reveals both t...

Using a single-mode glass fiber as a dispersive nonlinear medium, we observed hysteresis, period doubling and chaotic behavior of 10 ps laser pulses in a ring cavity. Some special timing logic allowed us to control all relevant parameters, and so for the first time the nonlinear dynamics were studied quantitatively. The general features were in agr...

An experimental setup for ultrafast switching measurements is described. The instrumental time resolution was measured to be ⩽100 ps. An analysis of the test circuit showed that it could be considered as an LRC network having a nonlinear ferroelectric capacitor. The switching and the nonswitching ferroelectric charges were shown to determine th...

The light power transmitted by a diffusively illuminated slit of finite thickness is observed to depend stepwise on the slit width. The steps have equal height and a width of one half the wavelength of the monochromatic light used. This novel diffraction phenomenon is the analogue of the quantization of the conductance of a point contact in a two-d...

In the case of two-dimensional diffuse illumination of a slit, it is predicted that the transmission cross section per unit slit length increases in stepwise fashion as a function of the slit width W, with steps of height lambda/2 occurring whenever W = n lambda/2 (n = 1, 2, 3, . . .) - that is, whenever a new mode is enabled in the slit. The obser...

Localization of waves is associated with the presence of interference effects in multiple scattering. In this paper we discuss light scattering experiments on strongly scattering random media consisting of small dielectric particles (TiO2, polystyrene) in a medium (airy water). Experimental observations include observation of interference in backsc...

Enhanced backscattering from a random medium resulting from interference is known as weak localisation. In the backscattered light three polarisation effects are observed: there is partial retention of polarisation, the polarised cone of enhanced backscattering is spatially anisotropic, and a slight enhancement is found in the depolarised light com...

DOI:https://doi.org/10.1103/PhysRevB.38.5063

Recently the interest in interference effects in multiple (elastic) scattering of waves has undergone an important revival due to the discovered connection with Anderson localization. In this paper we discuss a rigorous scalar wave theory as a model to represent the enhanced backscattering (weak localization) of light for finite slabs. In addition,...

Enhanced backscattering from a random medium resulting from interference is known as weak localisation. In the backscattered light three polarisation effects are observed: there is partial retention of polarisation, the polarised cone of enhanced backscattering is spatially anisotropic, and a slight enhancement is found in the depolarised light com...

We report on the dependence of enhanced backscattering of light in a random medium on sample thickness, mean free path, and size of scattering centers. Introduction of a new difference technique allows for independent observation of contributions from long and short light paths in a suspension of polystyrene spheres. A new anisotropy effect, which...

The experimental observation of weak localization of light is discussed and some general aspects of Anderson localization of light are treated.