摘要:
The present invention relates to encoding and decoding of information using materials that are mildly absorbing radiation over a wide range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. Examples of such encoding of information are bar codes and area markings. Information is encoded in markings on a base medium by depositing or intertexturing on the base medium a material where the surface dimensions, thickness and presence of the material contain the encoded information. The encoding utilizes a lower cost, more stable material than a material that is highly absorbing over a range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. However, since the material is mildly absorbing in the infrared range, the signal obtained by reflecting or transmitting infrared radiation from the markings will be less distinct. Thus, inventive methods are needed to ensure that the encoded information can be decoded. Two different approaches are disclosed; (a) detecting the absorption spectrum and comparing to the known spectrum of the material in order to detect the presence and surface dimensions of the material and (b) utilizing techniques to improve the signal-to-noise such as restricting the range of wavelengths, matched filters and narrowing the bandwidth.
摘要:
The present invention relates to encoding and decoding of information using materials that are capable of mildly absorbing radiation over a wide range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. Examples of such encoding of information are bar codes and area markings. Information is encoded in markings on a base medium by depositing or intertexturing on the base medium a material where the surface dimensions, thickness and presence of the material contain the encoded information. The encoding, as disclosed in this invention, utilizes a lower cost, more stable material than a material that is capable of highly absorbing over a range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. However, since the material used in this invention is mildly absorbing in the infrared range, the signal obtained by reflecting or transmitting infrared radiation from the markings will be less distinct. Thus, inventive methods are needed to ensure that the encoded information can be decoded. Two different approaches are disclosed; (a) detecting the absorption spectrum and comparing to the known spectrum of the material in order to detect the presence and surface dimensions of the material and (b) utilizing techniques to improve the signal-to-noise such as restricting the range of wavelengths, matched filters and narrowing the bandwidth.
摘要:
The present invention relates to encoding and decoding of information using materials that are capable of mildly absorbing radiation over a wide range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. Examples of such encoding of information are bar codes and area markings. Information is encoded in markings on a base medium by depositing or intertexturing on the base medium a material where the surface dimensions, thickness and presence of the material contain the encoded information. The encoding, as disclosed in this invention, utilizes a lower cost, more stable material than a material that is capable of highly absorbing over a range of infrared wavelengths and substantially non-absorbing in the visible wavelengths. However, since the material used in this invention is mildly absorbing in the infrared range, the signal obtained by reflecting or transmitting infrared radiation from the markings will be less distinct. Thus, inventive methods are needed to ensure that the encoded information can be decoded. Two different approaches are disclosed; (a) detecting the absorption spectrum and comparing to the known spectrum of the material in order to detect the presence and surface dimensions of the material and (b) utilizing techniques to improve the signal-to-noise such as restricting the range of wavelengths, matched filters and narrowing the bandwidth.
摘要:
A solid state, compression method for fabricating lenses, lens blanks, and lens components from materials ground into fine powders having mechanical properties the make them capable of being formed into cohesive monolithic masses that are low in scattering. The fine powders may be admixtures of host matrix materials and others which, when combined, provide preferred optical properties such as index and dispersion. Parts possessing transmission from within the range from the ultraviolet to the infrared are possible. The method is particularly suited to low temperature formation of aspheric lenses transmissive in the near and far IR.
摘要:
A directionally-oriented reflective device is optically coupled to a prism surface in a skin ridge pattern imaging system to reflect illumination light at relatively small angles, along an optical path to an imaging device, so that minimal light is lost from the optical system. Examples of such directionally-oriented reflective devices include, but are not limited to, echelon reflectors, faceted reflective surfaces, retroreflectors, aluminum paint, nacreous pigment, and slightly rough mirror surfaces.
摘要:
Diffuse “dark field” illumination and “bright field” illumination are each provided for a hand-held encoded symbology imager/reader; to be projected therefrom upon symbology disposed on a target (component part, goods, package, etc.). The imager/reader is encased in a housing ergonomically configured to be griped in more then one manner and to thus facilitate holding the imager/reader steady. The symbology to be imaged is targeted by a line that not only spots the symbology, but by extending a length commensurate with that of the symbology, indicates that the symbology is in the field of view of the imager/reader. A CCD, disposed to receive light reflected from the symbology, has its readout controlled so that only selected portions of the CCD need be analyzed for illumination and focusing purposes. To optimize imaging and decoding time, and to optimize use of power, readout from some portions of the CCD is accomplished in relatively rapid time by speeding up the readout of the CCD in some of its active area; while reverting back to a slower readout for data to be analyzed for illumination and focusing control and decoding purposes. In addition, special application of entropy principles facilitate determining the optimum focus and illumination conditions for the imager/reader.
摘要:
An optical viewfinder system comprising two optical elements, and a field stop or a reticle, to provide an image of a scene to a viewer, and further comprising a diffractive optical element to provide a clear, stationary image of the field stop or reticle to the viewer.
摘要:
A focusable imaging system particularly suitable for use in acquiring digital images for subsequent processing such as in a hand held, omnidirectional symbology or bar code reader by which linear and two dimensional (matrix, maxi-code) bar codes may be imaged over relatively long working distances. The imaging system includes an focusing objective taking lens and a two-dimensional photodetector that operate to form an image of an object such as a bar code in X and Y directions simultaneously and generate an electrical signal representative of the object or code for subsequent downstream processing by which information embedded in the object or bar code may be extracted. Focusing is achieved via a rotating disk that carries a plurality of optical shims or other light controlling surfaces to provide for different focus zones. A through-the-lens (TTL) targeting system is provided to visually assist the user in positioning the reader for a variety of code modalities to assure that a bar code or the like will be captured within the field of view and be sharply imaged on the photodetector when the lens is focused. Two different forms of artificial illumination are provided to accommodate nearby objects or codes that may be either specular or partially diffuse and more distant objects or codes where the reflection characteristics have less impact on image contrast. Elements of the photodetector are used to assess available light levels and activate the artificial illumination system when ambient light levels are low. Ranging through the lens using elements of the photodetector is included to provide information to set the focus of the objective lens in one of many possible focusing zones.
摘要:
A novel method and apparatus is disclosed for electronically sensing a negative and a positive in a novel integral film structure of the instant development type using light of different wavelengths so as to produce reflected light from the negative and the positive which are indicative of the luminance characteristics and the chrominance characteristics of the image. The novel integral film structure has a filter which allows the negative to be scanned. Specifically, the filter transmits incident infrared radiation to which silver halide emulsion layers are sensitive and blocks the transmission of radiation in the range of wavelengths to which the silver halide emulsion layers are sensitive.
摘要:
A novel method and apparatus is disclosed for electronically sensing a negative and a positive in a novel integral film structure of the instant development type using light of different wavelengths so as to produce reflected light from the negative and the positive which are indicative of the luminance characteristics and the chrominance characteristics of the image. The novel integral film structure has a filter which allows the negative to be scanned. Specifically, the filter transmits incident radiation in the range of wavelengths other than a select range of wavelengths to which silver halide emulsion layers are sensitive and blocks the transmission of radiation in the range of wavelengths to which the silver halide emulsion layers are sensitive.