Diffraction Products Inc
Business Identifier: NO Business Identifier is currently available for this company.
Public Profile:
Diffraction Products, Inc. (DPI) is in the business of producing high quality, precision gratings. The company employs two ruling engines. I. RULING ENGINE NO.I - Research for this ruling engine began in 1942, and construction was complete in 1952. The ruling engine consists of two nickel, semi-steel castings, each weighing about 1000 kg. The front casting supports the ruling mechanism while the rear casting carries the driving mechanism. Both castings are mounted on one pier, with separate three-point suspension systems for each. The engine design has been modified from the Rowland ruling engine in several key areas: The grating carriage can be regulated to remain the same for all sizes of grating substrates because of the use of two lead screws. A master screw, mounted conventionally, positions the grating carriage, while a slave screw, mounted three feet above the engine, carries the weight of the grating carriage and grating substrates by means of a suspension system. This arrangement ensures that the force exerted by the master leadscrew to remain the same for all sizes of grating substrates. 2. The leadscrew is mounted on its own bearings, separate from the mechanism used to index it. 3. The dividing gear, which is mounted on separate bearings is of globoid design, using the average spacing of 72 teeth for each indexing position. 4. The gratingcarriage, leadscrew and dividing gear are all mounted on sapphire bearing pads so that a very low coefficient of friction is maintained with high wear resistance. All other bearings of the engine are super-cushion oilite to minimize lubrication problems. 5. Ruling time for large gratings is decreased. A modified crank crank-lever action for reciprocation of the diamond carriage delivers one third more ruling strokes per minute than a machine using a simple crank motion, without increasing diamond speed. 6. The engine utilizes a very precise, electronically controlled motor drive. 7. The control system is based on the Zygo Double Pass Interferometer. This system enables the engine to rule gratings with either constant groove densities or variable groove densities. The pier on which this engine is supported extends 2 meters below the floor. The pier is completely isolated from any building vibrations by being encased in a concrete box, surrounded with a 61 cm thick layer of sand, and resting on a bed of sand 91 cm deep. The pier is further isolated inside this box by 10 cm thick slabs of vibration-absorbing cork. To ensure that the pier's center of gravity was ideally positioned, the pier was cast hallow, and 7.25 metric tons of metal punchings were added to bring the pier's weight to 11.8 metric tons. The top surface of the pier is faced with a hot-rolled steel plate, which provides the support for the hardened steel guides which orient the castings on the pier in relation to one another. 2. RULING ENGINE NO.2: - This engine employs a design and control system in which the ruling diamond of this engine remains stationary while the carriage moves beneath it on x-y air bearing ways. The motion of the x-axis (cutting axis) along the groove length is produced by momentum. There is no mechanical connection between the diamond and the carriage. The main carriage advances below the diamond at right angles to the grooves, controlled by continuous computer guidance using a scale for reference. This allows the positioning of the carriage to within 1 micron (accuracy of the scale). With this arrangement, it is possible to rule evenly spaced grooves, variable spaced grooves, and grooves where the angle of the face varies from groove to groove. The depth of each groove also can be varied. The engine is used to produce special reflectors, retro-reflectors, and beam splitters with surface finishes capable of being used in the ultraviolet region with very high efficiency. 3. THE LABORATORY: - Both engines are housed in a laboratory located 5.5 meters below the surface of a moraine hill. The walls and ceiling of the laboratory are 30 cm-thick concrete, and both the outer and inner surfaces of the entire building are insulated. The engine rooms are maintained at 20º ± .01º centregrade by a proportional temperature control system operating heaters distributed in the walls and ceilings.

 Synopsis: Awardee Business Condition
Year Founded IP Holdings
Employee Range VC funded?
Revenue Range Private/Public
 Most Recent SBIR Projects
Year Phase Agency Dollars Project Title
High Efficiency Low Scatter Echelle Grating