A medical imaging system provides simulataeous rendering of visible light and fluorescent images. The system may employ dyes in a small-molecule form that remains in a subject’s blood stream for several minutes, allowing real-time imaging of the subject’s circulatory system superimposed upon a conventional, visible light image of the subject. The system may also employ dyes or other fluorscent substances associated with antibodies, antibody fragments, or ligands that accumulate within a region of diagnostic significance. In one embodiment, the system provides an excitation light source to excite the fluorescent substance and a visible light source for general illumination within the same optical guide that is used to capture images. In another embodiment, the system is configured for use in open surgical procedures by providing an operating area that is closed to ambient light. More broadly, the system described herein may be used in imaging applications where a visible light image may be usefully supplemented by an image formed from fluorescent emissions from a fluorescent substance that marks areas of functional interest.

Medical imaging systems

Excitation light for normal light observation with wavelengths in the visible spectrum, which is output from a lamp, and excitation light with wavelengths in the infrared spectrum for exciting a fluorescent substance characteristic of being accumulated readily in a lesion are irradiated simultaneously to a living tissue, to which the fluorescent substance has been administered, through an endoscope. Fluorescence components are separated from light stemming from the living tissue by means of a separator such as a dichroic mirror, introduced to a first imaging device, and then imaged. Light components with wavelengths in the visible spectrum are introduced to a second imaging device and then imaged. Signals representing the images are subjected to signal processing, whereby a video signal is produced. For better diagnosis, two images are displayed while, for example, one of the images is superimposed on the other.

Fluorescent endoscope system enabling simultaneous achievement of normal light observation based on reflected light and fluorescence observation based on light with wavelengths in infrared spectrum

A content syndication platform, such as a web content syndication platform, manages, organizes and makes available for consumption content that is acquired from the Internet. In at least some embodiments, the platform can acquire and organize web content, and make such content available for consumption by many different types of applications. These applications may or may not necessarily understand the particular syndication format. An application program interface (API) exposes an object model which allows applications and users to easily accomplish many different tasks such as creating, reading, updating, deleting feeds and the like.

Content syndication platform

A contrast-based image fusion system and method of processing multiple images to form a processed or fused image including regions selected from one or more images. Images are divided into image regions. Portions of the images are filtered if necessary. A contrast map is generated for each image via a convolution kernel resulting in a contrast map with contrast values for each image region. Contrast values are compared and image regions are selected based on a selection criteria or process such as greater or maximum contrast. The selected image regions form the fused image. If necessary, the luminance of one or more portions of the fused image is adjusted. One sensor is selected as a reference sensor, and an average intensity of each region of the reference sensor image is determined across the reference sensor image. The intensity of one or more regions in the final image is adjusted by combining the determined average luminance values and intensity values of the final image.

Image fusion system and method

A computer-implemented method combines related source images, each represented by a set of digital data, by determining three-dimensional relationships between data sets representing related source images and creating a data set representing an output image by combining the data sets representing the source images in accordance with the determined three-dimensional relationships.

Combining digital images based on three-dimensional relationships between source image data sets

An x-ray examination apparatus includes an imaging arrangement, devised for performing fluoroscopy. Which has image sensors that are efficiently optically coupled with an x-ray sensitive radiation conversion screen. Consequently, the image sensors produce an electrical signal having a high signal-to-noise ration when low doses of x-radiation are administered. An x-ray conversion screen is provided with a tapetum filter so as to concentrate light in the forward direction. Furthermore, the x-ray conversion screen is preferably fitted with a light reflecting layer for reflecting light that has been reflected by the tapetum filter, said light reflecting layer being transparent for x-radiation. Further concentration of light in the forward direction is achieved by placing a light-transparent material having a suitable refractive index between the radiation conversion screen and lenses that concentrate the light onto the image sensors. Semiconductor image sensors in the form of charge-coupled devices are provided for converting a visible image into an electronic video signal. In order to improve the effectiveness of the CCDs, weak avalanching is applied so as to increase both sensitivity and signal-to-noise ratio of the sensors.

/pdf/x-ray-examination-apparatus-with-an-imaging-arrangement-4jkzmq1qo7.pdf

X-ray examination apparatus with an imaging arrangement having a plurality of image sensors

An x-ray imaging system provides automatic adjustment of x-ray tube voltage and current based on an identification and removal of background pixels in the image and a calculation of the functional relationship between voltage and current and dose for the particular imaged object as deduced from two exposures at different voltages. Real-time image distortion removal and image rotation are accomplished by computer processing using a generalized image transformation polynomial. Scatter in the image is reduced by calculating a scatter map based on a blurring of the received image and normalizing the scatter map to point scatter measurements made with an x-ray occluder eliminating direct exposure of certain areas of the image. Improved signal to noise ratio in a moving x-ray image is provided by averaging stationary portions of the image over a longer time than the moving portions of the image. A non-linear white compression function further reduced image noise by transforming the raw image to a gray scale having equal noise intervals.

X-ray imaging system

In this paper, new insights in the near infrared imaging process used in finger-vein recognition by developing a physical model are presented. A realistic phantom finger that mimics the living human finger and also includes veins has been developed to validate this model. NIR phantom finger images show that the phantom can emulate the optical properties of a living human finger and can provide ground truth for the locations of the veins. Through physical modeling, it is particularly learned that—besides blood and soft tissue—bone also plays an important role in generating reliable NIR finger-vein images. 

https://ris.utwente.nl/ws/files/276636378/Normakristagaluh_2022_Understanding_and_modeling_finger_v.pdf

Understanding and modeling finger vascular pattern imaging

Systems for atmospheric research and wireless communication use the High Frequency (HF) radio spectrum. At these frequencies, typically up to 20 MHz, the ambient electromagnetic noise is stronger than the noise generated by the receiver itself, thereby limiting the sensitivity of the instruments. Especially in urban areas, the noise level is high. In remote rural environments, where artificial noise sources are absent, a much lower noise level is observed. It has been shown that this noise arrives via ionospheric propagation and consists of impulsive noise from lightning and a background component that resembles additive white Gaussian noise. To establish the absolute field strength of this background noise component, a direction- and polarization-agnostic antenna is realized by adding the power of two orthogonal antenna elements in the digital domain. To suppress radio signals arriving via ionospheric propagation—of which the spectral and temporal aspects are not known a priori—a novel adaptive filter is demonstrated that separates the background noise from the radio signals in the joint frequency-time domain. This method is demonstrated using measurements from a polarimetric experiment on 7 MHz in a remote rural area in Catalonia. The results are submitted to the International Telecommunication Union for the validation of ambient noise models.

/pdf/separation-of-ambient-radio-noise-and-radio-signals-received-230cm9a1.pdf

Geert Jan Laanstra

Papers

X-ray examination apparatus with an imaging arrangement having a plurality of image sensors

X-ray imaging system

Understanding and modeling finger vascular pattern imaging

Separation of Ambient Radio Noise and Radio Signals Received via Ionospheric Propagation