Abstract: An identification mark constituted of irregularities is formed on the surface of a wafer, which is sealed with a resin layer and a dicing tape may be adhered to the backside. Multiple infrared units irradiate infrared rays towards the surface of the wafer from the backside thereof, wherein they transmit through the wafer and are then reflected at the interface between the resin layer and the surface of the wafer, thus producing reflected rays. An image pickup device picks up an image of the interface including the identification mark based on reflected rays. Optical axes of the infrared units extend to cross the surface of the wafer in different directions; hence, the image pickup device receives only a part of reflected rays, which are reflected at the interface in a prescribed direction. A polarizer can be arranged in proximity to the infrared unit or the image pickup device.

Abstract: A product tag system comprises: an RFID tag adapted for attachment to a product; a data store in the tag for bar code information relating to the product; a tag detacher for removing the tag from the product at a point of sale; an RFID tag reader for retrieving the bar code information from the tag when the tag is placed in the tag detacher; and, an display for presenting the bar code information in a form which can be scanned by a conventional bar code scanner, and/or in human readable form. A method for monitoring products comprise the steps of: attaching an RFID tag to a product; writing bar code information onto the tag; retrieving the bar code information from the tag at a point of sale; displaying the bar code information in a form which can be scanned by a conventional bar code scanner, and/or in human readable form; and, detaching the tag from the product.

Abstract: A collar for a drain pipe riser is provided for maintaining an annular space about the periphery of the riser during the pouring of a floor about the riser. The collar includes inner and outer sleeves separated by a plurality of knock-out webs. The inner sleeve is adapted to fit over the riser while the outer sleeve insures an annular space will be maintained about the riser during pouring of the floor. The webs can then be knocked out, and the inner sleeve and webs removed.