Sony S530D manual Three Laser Beams from One Laser

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	Single
1 . 1 cm	Focus
1 . 1 cm	Point

Info Layer

C D

D V D

Laser

B e a m

Objective

Lens

D V D

Laser

Light

	2 N D	1 S T
	Order	1 S T
	Order	Order
		Main
		Laser
		B e a m
	2 N D	1 S T
	Order	Order

To

Objective

Lens

Defraction

Grading

CD FOCUS CORRECTED

Three Laser Beams from One Laser

Although there is one laser, there are three spots of light on the disc’s information layer. The three spots are made by diffraction grading inside the laser assembly.

A diffraction grading is made of a glass sheet with lines etched on it form- ing channels. The channels are represented by the spaces between the dotted lines in the diagram. As the main laser beam passes through a channel, secondary light beams are produced. The first order beams are the strongest and these are the two additional (side) spots that pass through the objective lens onto the disc. These side spots are used for CD track- ing.

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Contents Course DVD-02 Course Description and Troubleshooting Page Table of Contents Processing Block Processing Laser Servo Test Mode KHM-220A DVD Optical BlockTroubleshooting Disc Identification Initial Sled Motor DriveDVD, LD, DTV Introduction to the DTS Audio FormatDVD, LD VHSChannel Receiver With DTS Decoder AC-3 Decoder What is DTS?What do I need to play the DTS surround format? CD/DVD PlayerAdaptive Predictive Coding Adpcm Can DVD movies contain both DTS and AC-3 audio tracks?How does DTS work? CompressionGlobal Bit Management MultiplexerPacker Compression BlockBoard Layout DVP DVD FeaturesServo Control Block DiagramPower Supply CommunicationsBlock Diagram ARP2 Video and Audio ProcessingBlock Diagram Power Consumption Power Supply BlockStandby Power Supply Main Power SupplyPower Supply Block Regulation Concept Standby OscillatorStart RunStandby Oscillator Main Oscillator EnableRegulation Main Oscillator Pcont Power ControlPlug IC201 IC202 Communications WaveformsPower Control Post Power on Check Power Control Parallel Data Communications BlockSerial Data Communications Block EEProm IC201 Serial Data CommunicationsSerial Bus Interface IC201Serial Data Communications Audio DSP IC501 Serial Data Communications Chip Select Line Parallel Data CommunicationsHGA IC601 Parallel Data Communication Communications from Another IC to IC202 Communications from IC202 to Other ICsParallel Data Communication Mechanism No Power Tray Removal From the BottomDisc Tray and Laser Platform Position Tilt Motor No Power Tray Removal From the TopSled Position Laser Focus CoilPower on Mechanical Sequence No Disc Power on Mechanical Sequence DVD Disc Page IC201 Communicates with System Control IC202 Tray Motor DriveInterface Controller IC201 Recognizes the Tray Button IC201 Turns On the DisplayTray Motor Drive Tray Position Switch Returns Information to IC201 Driver IC802 Translates the CommandIC202 Instructs Hybrid Gate Array IC601 Tray Motor Drive HGA IC601 Instructs Servo DSP IC701 Initial Sled Motor DriveInitial Sled Movement System Control IC202 uses HGA IC601Initial Sled Motor Drive Sled Still Sled Outward Servo DSP IC701 Issues Analog Commands to Driver IC802Initial Sled Motor Drive Sled Driver IC802 Sends Voltages to the Stepper Sled Motor Home Position DetectionSled Drive Mute/Inhibit Initial Sled Motor Drive Servo DSP IC701 to RF Amplifier IC001 Communications Laser ServoSystem Control IC202 and HGA IC601 Communications HGA IC601 to Servo DSP IC701 CommunicationsLaser Servo DVD Focus KHM-220A DVD Optical BlockCD Focus Three Laser Beams from One Laser TE +, TZC Photo DetectorsPage Sacd Disc Type Disc IdentificationOperation Disc Identification Concept Search FocusServo Focus System Control IC202 to HGA IC701 Focus DriveFocus Search Communications System Control IC202 to Servo IC701Focus Sdcps HGA IC601 to Servo IC701Focus Spindle Motor Kick ModeDVD Spindle Motor MDS CLV PB ModeMDP Spindle Motor Track Counting in Pause or Picture Jump Tracking ServoSystem Control IC202 Uses HGA IC601 Tracking Servo Following the Track IC Summary ChartSled Motor Drive PB Sled Movement to Another LocationSled Motor Drive PB ICs Involved Tilt ServoTilt UP Tilt to Mid PositionTilt Servo Manually Driving the Tilt Motor Power OFFDVD Playback Tilt Servo Audio/Video Processing Block Process Blocks RF Amp IC001 ProcessingProcessing Flash ROM IC205 Video Process CH34O Converters IC902, IC905 IC907CH78O CH12OAudio Processing Test Mode Access Test ModeTests Test Mode Access Clearing Emergency Codes Additional Test ModeSelf-Diagnostic Function Customer Error Codes Video Level AdjustmentPage No Power on TroubleshootingNo DVD PB CD PB OK No DVD OSD logoNo Disc PB No DVD DL PB other discs PB OK