Abstract: A method and apparatus are disclosed for measuring long bone density of small animals. A phosphor screen or plate is provided of a type that transduces incident ionizing radiation to emitted light. A small animal is positioned before the phosphor screen or plate and exposed to soft X-radiation having an energy level in the range of 11 to 16 Kev. Light emitted by the phosphor screen or plate is captured using a digital camera and a digital X-ray image is prepared of a long bone of the animal. The X-ray image is transformed into an X-ray density image and a region of interest is defined on the long bone in the X-ray density image. At least one row of pixels is scanned within the region of interest of the X-ray density image. A nonlinear least squares analysis of data obtained from the scanning step is conducted using a cylindrical model for the long bone within the region of interest.

Abstract: An imaging target, suited for use in multi-modal imaging systems, includes test patterns for testing quality of both focus and co-registration for multiple magnifications and multiple modalities of operation of a multimodal imaging system.

Abstract: A fluorescence reference plate for a fluorescence spectroscopic instrument is arranged with fluorescent layers having different excitation and emission characteristics. The fluorescent layers are ordered in the form of a stack for providing a flat-field calibration standard over multiple bands of wavelengths.

Abstract: An optical modulator which has substantially low loss and has an improvement in voltage reduction is disclosed having an electro-optic lithium niobate substrate. The substrate has first, second and third ridges extending along its surface. Extending along the first and second ridges are first and second waveguides. A first RF electrode extends over the first waveguide and a second slotted electrode including a first section extends over the second waveguide. A second section of the slotted extends parallel to and adjacent to the first section on the third ridge. In summary, this invention provides a slotted ground electrode wherein a slot is formed in the substrate between the slotted electrode.