Abstract: The invention relates to a compressor unit (200) for a refrigeration system using a refrigerant. The compressor (200) unit includes a centrifugal compressor (201) for compressing the refrigerant, wherein the compressor (201) has a discharge outlet (204) for discharging the compressed refrigerant, and a check valve (1; 100; 301a). An inlet (83) of the check valve (1; 100; 301a) is in fluid connection with the discharge outlet (204) of the compressor (201). In order to provide a more reliable and more quite compressor unit (200), the check valve (1; 100; 301a) is a nozzle check valve including a damping mechanism (41, 50; 50, 141), wherein a closing parameter of the check valve (1; 100; 301a) is between 50 s/m2 and 2000 s/m2, wherein the closing parameter is a closing time of the check valve (1; 100; 301a) divided by a port area of the check valve (1; 100; 301a).

Abstract: The present invention provides a spectroscopic system (100) for determining of a property of a biological structure in a volume of interest (120) of a person. The spectroscopic system (100) comprises a low cost objective lens (118) for directing an excitation beam into a volume of interest (120) and for collecting return radiation (124) from the volume of interest (120). After detection of the return radiation (124), i.e. the spectroscopic signals, a correction unit (106) performs the compensation of the aberrations of the spectroscopic signals introduced by the low cost objective lens (118). Since the aberrations of the objective lens (118) strongly depend on the lateral distance (122) of the volume of interest (120) from the optical axis (116) of the objective lens (118), the correction unit (106) makes effective use of a correction table (110) providing an assignment between correction values and various lateral positions (122) of the volume of interest (120).

Abstract: The invention provides an optical analysis system for efficient compensation of spectroscopic broadband back-ground, such as spectroscopic fluorescence background or background signals that are due to the dark current of a detector. The optical analysis system effectively provides multivariate optical analysis of a spectroscopic signal. It provides wavelength selective detection of various spectral components that are indicative of a superposition of spectroscopic peaks or bands and their broadband background. Additionally, the optical analysis system is adapted to acquire spectral components that predominantly correspond to the broadband background of the spectroscopic peaks or bands. Wavelength selective selection of various spectral components is performed on the basis of reconfigurable multivariate optical elements or on the basis of a position displacement of a spatial optical transmission mask.

Abstract: The present invention provides a spectroscopic system and a transmission based imaging system for a spectroscopic system as well as a probe head for a transmission based imaging system for a spectroscopic system and a corresponding transmission based imaging method. The spectroscopic system is preferably applicable to in vivo noninvasive blood analysis. Transmission based imaging makes use of a transmitted portion of an imaging or monitoring beam that has been transmitted through biological tissue. By means of transmission based imaging, a contrast decreasing impact of scattered radiation can be effectively reduced. Additionally, by arranging the imaging light source opposite to an objective lens of the spectroscopic system, unintended propagation of spectroscopic excitation radiation into free space can be effectively prevented.

Abstract: The present invention provides for a method of optical spectroscopy, in particular Raman spectroscopy for performing invasive or non-invasive blood analysis. The fluorescence component of return radiation which is received from a detection volume is eliminated which is enabled by the usage of a pulsed excitation light source. The pulse length is substantially shorter than the fluorescence life time Hence, the elimination of the fluorescence composent can be performed by time gating or by other electronics or optical means.

Abstract: The present invention provides an autofocus mechanism for a spectroscopic system that is adapted to determine a property of a volume of interest. The volume of interest has an optical property that varies with time. The invention provides measurement means that are adapted to measure the fluctuations of the optical property of the volume of interest for determining the position of the volume of interest. The spectroscopic system being further adapted to focus an excitation beam into the determined volume of interest and for collecting return radiation emanating from the volume of interest for spectroscopic analysis. Preferably, inelastically scattered radiation of an excitation beam is separated from elastically scattered radiation for spectroscopic analysis. The elastically scattered radiation of the excitation beam is in turn exploited in order to measure the fluctuations of the optical property of the volume of interest.

Abstract: The present invention provides a spectroscopic system and in particular a fiber optic probe for in vivo detection of vulnerable atherosclerotic plaque inside the cardiovascular system of a patient. Detection of vulnerable plaque is based on a location dependent measurement of concentration levels of cardiac marker molecules flowing in the blood stream. Concentration level determination is preferably based on surface-enhanced Raman spectroscopic techniques providing sufficient sensitivity for determination of these concentration levels. Acquisition of spectroscopic data during moving of the fiber optic probe through the cardiovascular system with controlled velocity allows to precisely locate vulnerable plaque in the cardiovascular system.

Abstract: The present invention provides a spectroscopic system for determining a property of a fluid flowing through a volume of interest underneath the surface of the skin of a patient. The spectroscopic system comprises a probe head that has at least an objective for directing an excitation beam into the volume of interest and for collecting return radiation. The spectroscopic system has further a base station having at least a spectroscopic analysis unit and a power supply. The system makes use of a beam combination unit, a filter unit and a focusing unit for combining and separating a variety of different optical signals and for precisely positioning the optical signals inside the volume of interest. The beam combination unit, the filter unit and the focusing unit can be variably implemented inside the probe head or inside the base station depending on a specific applications of the spectroscopic system, thereby allowing for a flexible and compact design of the probe head.

Abstract: The present invention provides an optical analysis system for determining an amplitude of a principal component of an optical signal. The principal component is indicative of the concentration of a particular compound or various compounds of a substance that is subject to spectroscopic analysis. The optical signal is subject to wavelength selective weighting and wavelength selective spatial separation specified by a weighting function. The optical signal is preferably separated into two parts that corresponding to a positive and negative spectral band of the weighting function, respectively. The separation provides separate detection of the separated parts of the optical signal without significant loss of intensity, thereby providing an improved signal to noise ratio of the determined principal component. Separation and weighting of the optical signal is realized by two multivariate optical elements.

Abstract: The present invention enables to determine the property of a fluid, such as for the purposes of in vivo blood analysis. First the position of a volume of interest through which the fluid flows is determined by means of an optical detection step by making use of an objective. Preferably the optical detection step is an imaging step. Next the objective is moved to bring the focal point of the objective to the volume of interest. In this position an optical spectroscopic step is performed. This has the advantage that the measurement beam for performing the optical spectroscopy travels along the optical axis for optimum efficiency.

Abstract: An analysis apparatus, in particular a spectroscopic analysis apparatus, comprises an excitation system for emitting an excitation beam to excite a target region. A a monitoring system images the target region. The monitoring system being arranged to produce a contrast image in a contrast wavelength range and produce a reference image in a reference wavelength range. the contrast image and the reference image are compared to accurately identify the target region, notably a capillary blood vessel in the patient's skin.

Abstract: The present invention relates to a catheter head comprising: means (104, 108; 306, 304; 320, 322; 326; 338) for directing of radiation to a blood detection volume (220, 310), means (104, 108; 306, 304; 320; 322; 326; 332, 334, 330; 338) for receiving of return radiation from the blood detection volume, means (104; 306; 330) for transmitting of the return radiation to means (122) for analysis of the return radiation for determination of at least one property of the blood.

Abstract: The present invention relates to an analysis apparatus, in particular a spectroscopic analysis apparatus, for analyzing an object, such as blood of a patient, and a corresponding analysis method. To aim the confocal detection volume inside a blood vessel orthogonal polarized spectral imaging (OPSI) is used to locate blood capillaries in the skin. An imaging system (img) with slightly shifted imaging planes (i1, i2) for OPS imaging of blood vessels is proposed to provide auto-focusing. The confocal Raman detection plane (dp) is located in between these two imaging planes (i1, i2). Based on measured amount of defocus for the imaging planes (i1, i2), the focusing of the imaging system (img), the excitation system (exs) for exciting the target region and the detection system (dsy) are adjusted such that the difference of the amount of defocus equals a predetermined amount so that the confocal detection plane (dp) is located inside the blood vessel (V).

Abstract: A monitoring system for dark-field imaging of a target area (72) below a surface (70) of an object, e.g., capillary vessel under the surface of the skin of a patient, comprises an illumination optical system (31), an imaging system (35), and a selective optical interception system for suppressing illumination light returning from the region between the surface of the object and the target area. The interception system may comprise crossed polarizers (32, 37) in the illumination and imagining paths, respectively, and/or an aperture stop (51) arranged to intercept a central portion of the returning imaging beam. Alternatively, the illumination and imaging paths subtend an angle and the illumination focus and the imaging focus are displaced relative to each other. The monitoring system may be comprised in an analysis apparatus further comprising a spectroscopy system having an excitation system and a detection system.

Abstract: A lithographic apparatus includes a radiation system that provides a beam of radiation, and a support structure that supports a patterning structure. The patterning structure is configured to pattern the beam of radiation according to a desired pattern. The apparatus also includes a substrate support that supports a substrate, and a projection system that projects the patterned beam onto a target portion of the substrate. The projection system includes an optical element that has a beam exit area through each of which the patterned beam passes. The apparatus further includes a fluid cleaning system that cleans a fluid to be introduced into a region in between the optical element and the substrate. The fluid cleaning system includes a fluid inlet, a fluid outlet, and a cleaning zone disposed between the inlet and outlet. The cleaning zone includes a nucleated surface provided with a plurality of nucleation sites.

Abstract: The present invention provides for an apparatus and a method for determining a property of a fluid which flows through a biological tubular structure, such as blood flowing through a capillary vessel (112) under the skin (114). This enables in vivo non-invasive blood analysis. An objective (108) having a variable numerical aperture (116) is used to enable automatic detection of a blood vessel (112) and to provide a high signal to noise ratio of the return radiation for the purposes of the spectroscopic analysis and to provide a small detection volume that fits completely within the target region.

Abstract: A lithographic apparatus is disclosed. The apparatus includes a radiation system that provides a beam of radiation, and a support structure that supports a patterning structure. The patterning structure is configured to pattern the beam of radiation according to a desired pattern. The apparatus also includes a substrate support that supports a substrate, and a projection system that projects the patterned beam onto a target portion of the substrate. The projection system includes an optical element that has a beam entry area and an optical element that has a beam exit area through each of which the patterned beam passes. The apparatus further includes a nucleated surface that is associated with the projection system on which a plurality of nucleation sites are provided. The surface is disposed away from at least one of the beam entry area and the beam exit area.

Abstract: The optical analysis system (20) for determining an amplitude of a principal component of an optical signal comprises a multivariate optical element (10) for reflecting the optical signal and thereby weighing the optical signal by a spectral weighing function, and a detector (9, 9P, 9N) for detecting the weighed optical signal. The optical analysis system (20) may further comprise a dispersive element (2) for spectrally dispersing the optical signal, the multivariate optical element being arranged to receive the dispersed optical signal. The blood analysis system (40) comprises the optical analysis system (20) according to the invention.

Abstract: The present invention relates to an analysis apparatus, in particular a spectroscopic analysis apparatus, for analyzing an object, such as blood of a patient, and a corresponding analysis method. To aim the confocal detection volume inside a blood vessel orthogonal polarized spectral imaging (OPS imaging) is used to locate blood capillaries in the skin. Image processing means (ipm) determining image characteristics, which indicate if an imaging system (img) for imaging the object is focused on the object (obj) to be analyzed, from a detected image. Said image processing means (ipm) are preferably adapted for determining the amplitudes of spatial frequencies corresponding to typical characteristics of the object (obj) from a detected image, or for determining the maximum contrast present in a detected image.

Abstract: A lithographic apparatus is disclosed. The apparatus includes a radiation system that provides a beam of radiation, and a support structure that supports a patterning structure. The patterning structure is configured to pattern the beam of radiation according to a desired pattern. The apparatus also includes a substrate support that supports a substrate, and a projection system that projects the patterned beam onto a target portion of the substrate. The projection system includes an optical element that has a beam entry area and an optical element that has a beam exit area through each of which the patterned beam passes. The apparatus further includes a nucleated surface that is associated with the projection system on which a plurality of nucleation sites are provided. The surface is disposed away from at least one of the beam entry area and the beam exit area.