Chapter 55-115.3.4 Controlling the Scanning Lamp5.3.4.1 Scanning Lamp 0013-8584Color iR C3380G / Color iR C2880G / Color iR C3380i / Color iR C3380 / Color iR C2880i / Color iR C2880 / iR C3480 / iR C3480i / iR C3080 / iR C3080i / iRC2550The machine's scanning lamp is a xenon lamp, in which xenon gas is sealed inside a tube. Along the glass tube are 2 electrodes, while the inside the glass tube iscoated with phosphorous material. When a high-frequency voltage is applied to the electrodes, electrons occur within the gas, thus causing the phosphorous materialto emit light.F-5-155.3.4.2 Overview 0013-8586Color iR C3380G / Color iR C2880G / Color iR C3380i / Color iR C3380 / Color iR C2880i / Color iR C2880 / iR C3480 / iR C3480i / iR C3080 / iR C3080i / iRC2550The scanning lamp is controlled for the following, and is composed of the items indicated:- activation/de-activation- error detectionF-5-165.3.4.3 Activation Control 0013-8587Color iR C3380G / Color iR C2880G / Color iR C3380i / Color iR C3380 / Color iR C2880i / Color iR C2880 / iR C3480 / iR C3480i / iR C3080 / iR C3080i / iRC2550The scanning lamp is turned on/off using the drive signal (LAMP_ON) generated by the CPU of the reader controller PCB. In response to the signal, the inverterPCB uses the drive voltage (+16 V) from the reader controller PCB to generate high-frequency voltage in the activation control circuit to turn on the xenon lamp.5.3.4.4 Error Detection 0013-8588Color iR C3380G / Color iR C2880G / Color iR C3380i / Color iR C3380 / Color iR C2880i / Color iR C2880 / iR C3480 / iR C3480i / iR C3080 / iR C3080i / iRC2550An error in the intensity of the lamp is checked against the presence/absence of a fault when the lamp is initially tuned on (e.g., at time of shading correction).E225 (CIS intensity error)- fault in the inverter PCB- fault in the reader controller PCB- fault in the contact image sensor (CIS)- fault in the flexible cable (poor contact)5.3.5 Detecting the Size of Originals5.3.5.1 Overview 0013-8589Color iR C3380G / Color iR C2880G / Color iR C3380i / Color iR C3380 / Color iR C2880i / Color iR C2880 / iR C3480 / iR C3480i / iR C3080 / iR C3080i / iRC2550The machine identifies the size of an original based on the measurements it takes of the light reflected by the original at specific points of the CCD (inside the CIS)and the output of the reflection sensor.- main scanning direction: CCD (4 points for AB; 3 points for Inch)- sub scanning direction: reflection photosensor (1 point for AB; 1 point for Inch)1) External Light Search (main scanning direction only)While keeping the scanning lamp on, the machine measures the level of light at specific points of the CCD for main scanning direction.2) Detecting the Sensor Output LevelThe machine turns on the scanning lamp, and measures the CCD levels at individual points of detection in main scanning direction.The machine also turns on the reflection photosensor and measures its output for sub scanning direction.FluorescentmediumElectrodeOpeningElectrodeElectrodeElectrodeGlass tube1233211231234Inverter PCBActivationcontrol circuitReader controller PCBCPUGNDLANP_ON14.5VJ5015J5018 J512Xenon tubeCIS
