Abstract: An apparatus which develops a latent image with marking particles. The apparatus includes a developer roller which transports the marking particles closely adjacent to the latent image. As the marking particles are deposited on the latent image, the developer roller senses the charge thereon. In response to the sensed charge of the marking particles, additional marking particles are dispensed into the chamber of the housing for subsequent use by the developer roller.

Abstract: An apparatus in which the developability of electrostatically charged particles in a mixture of particulate material is measured. The apparatus includes a transparent member positioned closely adjacent to a developer roller of an electrophotographic printing machine. Electrostatically charged particles are attracted from the particulate mixture being transported by the developer roller to the member. A beam of energy is transmitted through the member. The intensity of the internally reflected beam is detected and a signal generated indicative of the quantity of charged particles adhering to the member.

Abstract: Apparatus for sensing deposition of a thin film layer of a material from a source onto a substrate having a carriage assembly including a predetermined number of apertures for selectively passing predetermined portions of a material from the source along each of a plurality of predetermined paths located in the proximity of the substrate under conditions correlated to that under which the material is deposited through a deposition path onto the substrate, inhibiting elements positioned relative to the carriage assembly for selectively inhibiting passage of predetermined portions of the material through a selected number of the predetermined number of the apertures, and a monitior for monitoring a selected parameter of the thin film material which is passed through other than the selected number of apertures of the carriage assembly wherein the monitor includes a plurality of detectors one of each of which is positioned along one of the plurality of predetermined paths and being adapted to sense a predetermine

Abstract: An apparatus for regulating the evaporation rate of oxidizable substances in reactive vacuum deposition by the metered addition of oxygen to a vacuum deposition chamber during deposition, wherein the addition of oxygen to a predetermined value, the pressure "p" in the vacuum chamber is measured, and the evaporation rate "r" for any pressure changes is regulated such that the ratio of pressure to evaporation rate p:r is maintained substantially constant.

Abstract: A method and an apparatus for controlling the content of an electroless plating bath such as an electroless nickel plating bath such that the bath is useable for an extended period of time without remaking are disclosed.

Abstract: A method and an apparatus for controlling an electroless plating bath such as an electroless nickel plating bath capable of using the bath for an extended period of time without remake are disclosed.

Abstract: A method and an apparatus for controlling the content of an electroless plating bath such as an electroless nickel plating bath such that the bath is usable for an extended period of time without remaking are disclosed.

Abstract: Apparatus for forming thin-film, large area solar cells having a relatively high light-to-electrical energy conversion efficiency and characterized in that the cell comprises a p-n-type heterojunction formed of: (i) a first semiconductor layer comprising a photovoltaic active material selected from the class of I-III-VI.sub.2 chalcopyrite ternary materials which is vacuum deposited in a thin "composition-graded" layer ranging from on the order of about 2.5 microns to about 5.0 microns (.congruent.2.5 .mu.m to .congruent.5.0 .mu.

Abstract: An apparatus having an article counter, a set-point register and a comparator, and at least one electrode for detecting solution pH, with a controlled system adapted to add pre-selected amounts of replenishing solution to the cleaning and treating baths controlled by the system when indicated by coincidence between the number in the pre-set counter and the number in the article counter, in response to system pH, whereby the solutions being replenished will retain predetermined characteristics throughout an extended operating life. A method which comprises sampling solution pH counting the articles being treated and replenishing treatments and cleaning solutions in response to article count and pH or other solution condition from time to time to maintain desired process characteristics.

Abstract: Process and apparatus for the staining of biological samples in which fluids of differing specific densities are successively introduced to the samples comprises a closed chamber to receive the samples for treatment, the chamber being provided with flow passages at the top and bottom and is in communication with an under pressure generating device so that fluids may be introduced into the chamber either from the top or the bottom depending upon whether a succeeding fluid is of lesser, or greater, specific density than the preceding fluid.

Abstract: A magnetic brush developing system for electrostatic duplication uses a developer having a magnetic carrier and non-magnetic toner which is transferred by the brush to an electrostatic image. A analog signal is derived using a Hall sensor in contact with the brush and adjacent to a magnet of the brush. The location of the sensor after and downstream of the transfer point provides information in the signal both as to the absolute value of the concentration (ratio of toner to carrier by weight) as well as the rate of transfer of the toner to the electrostatic image. These signals are used to control the supplying of replenishment toner to the developer only when the concentration of toner drops below a predetermined desired value and then at a rate commensurate with the rate of transfer of toner to the electrostatic image.

Abstract: A method and an apparatus for controlling an electroless plating bath such as an electroless nickel plating bath such that the bath is useable for an extended period of time without remaking are disclosed.

Abstract: A toner concentration detecting apparatus is disclosed wherein developing powder including magnetic carrier and pigmented toner is carried on a magnet roller and transported thereby to a surface of a photosensitive drum, and after development a portion of the developing powder is removed off the surface of the magnet roller and passed through a hollow body containing a detection coil to determine a concentration of the toner in the developing powder based on a magnitude of an inductance of the detection coil. A flow condition of the developing powder is at the same time determined by detecting a rippled voltage induced by the detection coil. Accuracy of detection is enhanced by an electric circuit for pulsating the rippled voltage and counting the number of pulses produced thereby. The flow of the developing powder is accelerated by a vibrator mounted on the hollow body responding to an output signal of the electric signal if the flow of developer powder stops.

Abstract: A developer level sensor installed on the sidewall of a developer container in a developing apparatus consists of an oscillator circuit with multiple coils, the mutual inductance of which is adjusted by a moveable electric conductor. The lower limit level of developer sensed may be adjusted by the positioning of a control plate.

Abstract: The intensity of development of latent images on dielectric receptor sheets in a liquid bath which contains a dispersion of toner particles and fills a vessel between two electrodes one of which supports a sheet in such a way that the latent image faces the other sheet is regulated by measuring the current which flows between the electrodes in response to insertion of a fresh sheet between the electrodes, comparing the measured result with a preselected reference value, and evacuating the bath from the vessel to thereby terminate the development when the ratio of measured result to the reference value is one-to-one or another preselected ratio.

Abstract: A toner concentration detecting apparatus comprises a rotatable probe having a toner-receiving face, a case housing the probe, means attached to the case for detecting an amount of toner on the toner-receiving face, and a port formed in the case for discharging stray toner particles from the case. The toner-receiving face is put in contact with a magnetic brush of a developer mechanism, separates toner particles from a developer and receives them. The detecting means includes a light-emitting element for applying light to the toner-receiving face and a light-receiving element for receiving the light reflected by the toner-receiving face and converting the light into an electric signal. The stray toner discharging port extends in the direction in which acts centrifugal force generated by the rotation of the probe and is located near the light-emitting and light-receiving elements.

Abstract: An apparatus for detecting the concentration of toner particles contained in the developing powder is disclosed wherein the developing powder comprising a mixture of magnetic carrier particles and the toner particles is transported while being adsorbed by a magnet roll, and rubbing an electrostatic recording surface lightly to develop an electrostatic latent image. After development, the developing powder is separated from the magnet roll, flows along a guide path, and forms a magnetic path for a flat detecting coil with the flat surfaces thereof placed in the guide path in the same direction as the flow of the developing powder. In response to the magnitude of the inductance of the detecting coil, an electrical circuit produces an electrical signal corresponding to the mixing ratio between the magnetic carrier particles and the toner particles in the developing powder.

Abstract: A toner concentration control device comprising a toner supply mechanism for supplying toner to a developing device, conveying means for conveying the developer, detecting means for optically detecting an amount of the toner adhering to a conveying surface of the conveying means and a control mechanism for controlling the toner supply mechanism based on the detected amount of toner. Thus, an amount of fresh toner corresponding to an amount of toner spent by development is supplied from the toner mechanism to a developer in the developing device to maintain a constant toner concentration in the developer.

Abstract: Epitaxial layers of single crystals of gallium arsenide and similar compounds are formed by vapor deposition. A carrier gas flow is passed through a liquid halide of a group VB material to obtain a first vapor having a halogen, carrier gas and group VB material. The carrier gas flow is monitored and adjusted to obtain a predetermined mass of halogen and second material in this raw vapor. A final reactor input vapor is obtained with constant concentration and constant flow going into a reactor by monitoring the total volume of carrier gas in the raw vapor as added per unit of time and adjusting the raw vapor by adding a volume of additional carrier gas to a predetermined value to form a final reactor input vapor. The reaction and deposition of the epitaxial layer is then carried out in a reactor.

Abstract: A powder density control means is provided for use in a photocopier machine of the type in which a photoconductor is charged in accordance with an image to be recorded thereon and is developed by contact with a toner powder attracted thereto from a mixture of carrier particles and toner powder carried by a developer assembly including a replenishment means for periodically adding toner powder. A high value resistance and a bias supply are serially coupled to a magnetic brush of the developer assembly. The voltage across the magnetic brush provides an indication of how heavily the latent image on the photoconductor is being toned. The change in magnitude of the voltage on the brush is sensed and when a predetermined amount of voltage change is detected, an additional amount of toner powder is supplied by the replenisher to the developer unit for such change.

Abstract: The effective concentration of an electroactive ingredient of a coating solution is determined, and may be restored to a desired level, in response to deviations in the voltammetric current sensed at an indicating electrode comprised of a noble metal.

Abstract: Apparatus and a method are disclosed for replenishing an electroless plating bath with those of its components which are consumed during plating operation, in order that the concentration of components be maintained as nearly constant as possible in the working bath. The system involves withdrawing from the bath a small sample stream at fixed rate, and subjecting this automatically to a sequence of analyses. The system is particularly adapted to control of electroless copper solutions comprising copper ion, hydroxide and formaldehyde as the consumable components. Sequential analyses are made of the sample stream for these components using instrumentation to control actuators which introduce replenisher solutions into the plating tank in response to signals generated by the instruments whenever deviation occurs from a pre-set level. Standardized test solutions of known concentration and rate of feed are introduced into the test stream to optomize test conditions during the analyses.