Abstract: A hardware identification system is provided in a bar code reading arrangement including a main body and a plurality of modular detachable scanning heads connectable to the main body dependent on the application desired for the reader. Each of the heads includes a voltage divider dividing identification voltage and the main body includes a microprocessor including an analog to digital converter which reads the identification voltage, converts it to a digital signal and compares the identification voltage against a look-up table of identification voltages and their associated hardware element to identify the module type. Alternatively, or in addition, the module may be similarly configured to identify the main body by virtue of an identification voltage defined by a voltage divider in the main body. Alternatively the hardware identification system includes an electronic subassembly such as a PC board used for example in computer systems for automatic identification of hardware.

Abstract: A high-reliability optical reading apparatus for reading a latent image mark capable of accurately reading the code information of a latent image mark. The optical reading apparatus comprises a light-projecting light member for projecting on a surface of the latent image mark, the light having a wavelength to excite a fluorescent substance contained in the latent image mark having desired information; and a light-receiving member for receiving fluorescence emitted from the surface of the latent image mark. A range in which the latent image mark can be read is formed by setting a point at which the optical axis of the light-projecting member and that of the light-receiving member intersect with each other as a reference. An intersection angle between the two optical axes is preferably in the range of from 10.degree. to 40.degree..