Alpes Lasers Cascade Laser Starter Kit manual

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Bom manual de uso

As regras impõem ao revendedor a obrigação de fornecer ao comprador o manual com o produto Alpes Lasers Cascade Laser Starter Kit. A falta de manual ou informações incorretas fornecidas ao consumidor são a base de uma queixa por não conformidade do produto com o contrato. De acordo com a lei, pode anexar o manual em uma outra forma de que em papel, o que é frequentemente utilizado, anexando uma forma gráfica ou manual electrónicoAlpes Lasers Cascade Laser Starter Kit vídeos instrutivos para os usuários. A condição é uma forma legível e compreensível.

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A palavra vem do latim "Instructio" ou instruir. Portanto, no manual Alpes Lasers Cascade Laser Starter Kit você pode encontrar uma descrição das fases do processo. O objetivo do manual é instruir, facilitar o arranque, a utilização do equipamento ou a execução de determinadas tarefas. O manual é uma coleção de informações sobre o objeto / serviço, um guia.

Infelizmente, pequenos usuários tomam o tempo para ler o manual Alpes Lasers Cascade Laser Starter Kit, e um bom manual não só permite conhecer uma série de funcionalidades adicionais do dispositivo, mas evita a formação da maioria das falhas.

Então, o que deve conter o manual perfeito?

Primeiro, o manual Alpes Lasers Cascade Laser Starter Kit deve conte:
- dados técnicos do dispositivo Alpes Lasers Cascade Laser Starter Kit
- nome do fabricante e ano de fabricação do dispositivo Alpes Lasers Cascade Laser Starter Kit
- instruções de utilização, regulação e manutenção do dispositivo Alpes Lasers Cascade Laser Starter Kit
- sinais de segurança e certificados que comprovam a conformidade com as normas pertinentes

Por que você não ler manuais?

Normalmente, isso é devido à falta de tempo e à certeza quanto à funcionalidade específica do dispositivo adquirido. Infelizmente, a mesma ligação e o arranque Alpes Lasers Cascade Laser Starter Kit não são suficientes. O manual contém uma série de orientações sobre funcionalidades específicas, a segurança, os métodos de manutenção (mesmo sobre produtos que devem ser usados), possíveis defeitos Alpes Lasers Cascade Laser Starter Kit e formas de resolver problemas comuns durante o uso. No final, no manual podemos encontrar as coordenadas do serviço Alpes Lasers na ausência da eficácia das soluções propostas. Atualmente, muito apreciados são manuais na forma de animações interessantes e vídeos de instrução que de uma forma melhor do que o o folheto falam ao usuário. Este tipo de manual é a chance que o usuário percorrer todo o vídeo instrutivo, sem ignorar especificações e descrições técnicas complicadas Alpes Lasers Cascade Laser Starter Kit, como para a versão papel.

Por que ler manuais?

Primeiro de tudo, contem a resposta sobre a construção, as possibilidades do dispositivo Alpes Lasers Cascade Laser Starter Kit, uso dos acessórios individuais e uma gama de informações para desfrutar plenamente todos os recursos e facilidades.

Após a compra bem sucedida de um equipamento / dispositivo, é bom ter um momento para se familiarizar com cada parte do manual Alpes Lasers Cascade Laser Starter Kit. Atualmente, são cuidadosamente preparados e traduzidos para sejam não só compreensíveis para os usuários, mas para cumprir a sua função básica de informação

Índice do manual

  • Página 1

    Quan tum Cascade Laser Starter Kit Instruction s Man ual (W eb v ersi on) CA UTION Before using the Qua n tum Ca scade Laser Starter Kit, read this do cumen tation and take spe cial note of all sa fet y instructions[...]

  • Página 2

    Con ten ts 1 Iden tification 4 1.1 Document . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2 Limited waran ty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2 General 5 2.1 Chapter ov erview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [...]

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    2 4.6.5 Laser peak voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 4.6.6 Average dissipatio n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 4.6.7 Accuracy considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 4.7 QCL pulser timing unit (TP G128) . . . . . [...]

  • Página 4

    3 10 App endix 55 10.1 Bias Circut (”Bias-T”) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 10.1.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 10.1.2 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 10.1.3 Specifica[...]

  • Página 5

    Chapter 1 Iden tification 1.1 Do cumen t Quantum Cascade Laser Starter Kit Instructions Manual. W eb V ersion 3.1 02.0 7 Man ufacturer Alpes Las ers SA 1-3 Passag e Max-Meuron CP 1766 CH-2001 Neuchˆ a tel T el. ++41 32 7299 510 F a x. ++ 41 32 72 13619 ht tp://www.alp eslaser s.ch info@alp eslasers.ch 1.2 Limited w aran t y Alpes Lasers SA will a[...]

  • Página 6

    Chapter 2 General 2.1 Chapter o v erview This chapter giv es basic information o n system func- tions, sp ecifications and do cumentation. 2.2 Generaliti es The indications in the present Instructions Manual, in particula r the safety instructions m ust b e co m- plied with. 2.3 Compliance The Q uant um Cas cade Laser Starter Kit has b een designe[...]

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    Starter Kit Instruction Manual General 6 2.4 Glossary The following terms, among others , are used in this Instructions Manual. 2.4.1 P ersons P ersonnel Personnel refers to all p erso ns who carry o ut any activit y with the instrumentation and meet the manuf acturer’s requirements about pe rsonnel to run those activities and have been ther efor[...]

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    Starter Kit Instruction Manual General 7 2.5 T yp ographic con ve n tions The following styles are used in this manual. Description sty le This st yle, used in relation with a num ber in il- lustrations (figures) is preceded by the cor resp ond- ing n umber: Example: (1) First item. (2) Second item. (3) etc... Commands sty le All so ft ware comman[...]

  • Página 9

    Starter Kit Instruction Manual General 8 Pro cedure effects sty le The pro cedure effects are describ ed by using the following sym b ol , → . Example: [1] Click on the Delete Sample icon. , → The messa ge Do you r e al ly want to delete the sample ? app ears . Cross references style This style is used to help the p erso nnel to find other i[...]

  • Página 10

    Starter Kit Instruction Manual General 9 Note st yle Used when the p ersonnel attention m ust b e dr awn to a par ticular op eration or information. Example: Note: The lab or atory housing LLH100 makes availab le two outputs giving ac c ess t o these voltage. Caution st yle Used to preven t the p ersonnel from any danger or hazardous situation. No [...]

  • Página 11

    Chapter 3 Safet y Instructions 3.1 Chapter o v erview This chapter sets out safety instructions for ensur- ing safe and trouble-fr ee opera tion of the system describ ed in this ma n ual. 3.2 In tro duction 3.2.1 Principle The p erso nnel must hav e read a nd understo o d this do cumen tation b efore carrying o ut any activity what- so ever with th[...]

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    Starter Kit Instruction Manual Safety Instructions 11 3.3 General safet y instructions • Never attempt t o use a system for purp oses other than those detailed in this manual. • Never attempt to use a system in conjunc- tion with o ther instrument s without obtain- ing prior information and approv al from the manuf acturer. • Never attempt to[...]

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    Chapter 4 Description 4.1 Chapter o v erview This chapter gives a basic descr iption of the Q uan- tum Casca de Laser Starter Kit system a nd its com- po sition. 4.2 System Comp osition The Quantum Cascade Laser Starter Kit is made up of the following items: (1) La bor atory Lase r Ho using (LLH10 0) (2) T emperature Controller (TCU151) (3) QCL pul[...]

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    Starter Kit Instruction Manual Description 13 4.3 DFB and FP Qu an tum Cascade Lasers 4.3.1 Description Quantum Cascade La sers (QCL) a re unip olar lasers emitting in the mid-infrared from 4 to 17 microns. The laser is a ridge of InGaAs and AlInAs grown on InP pr oviding gain and a F abry-Perot cavit y in order to build the laser o scillation up. [...]

  • Página 15

    Starter Kit Instruction Manual Description 14 4.3.3 Specifications F a r field elliptical (FWHM): V e rtical: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 ◦ Horizontal: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .[...]

  • Página 16

    Starter Kit Instruction Manual Description 15 4.3.4 Electrical mo del The QCL can be mo delised in a R C circuit. Electrical mo del c haracteristics The v a lues given below apply for a 10 µ m laser wa velength. Note: V oltage and r esistor values m ay vary ac c or ding to t he typ e of laser. R1 : . . . . . . . . . . . . . . . . . . . . . . . . .[...]

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    Starter Kit Instruction Manual Description 16 4.4 Lab oratory Laser Housing(LLH100) 4.4.1 Description The Lab orator y Laser Housing is a Thermo-E lectric co oled b ox which encapsulates the Q uantu m Cas- cade Laser. The internal tempera ture is controlled by a PT- 100 sensor a nd heat is dissipated by air or water. The LLH10 0 is desig ned to ea [...]

  • Página 18

    Starter Kit Instruction Manual Description 17 LLH100 in ternal view The La bo ratory Las er Housing includes the follow- ing items: (1) LLH100 top cov er (2) PET U-shap ed holder (3) Gilded copper contact (UP and DN) (4) Laser (5) Laser r eceptacle 4.4.2 Specifications Maximum P eltier current (with w ater cooling): . . . . . . . . . . . . . . . .[...]

  • Página 19

    Starter Kit Instruction Manual Description 18 4.4.3 Thermo-Electric Co oler (TEC) and PT100 connections The pin 1 is recognise d b y a circle aro und it and a thin no on ended circle starts from pin one and turns around the pins until pin 6. (1) Pin 1: + Peltier elemen t (2) Pin 2 : - Peltier element (3) Pin 3 : I+ PT1 00 (4) Pin 4 : Sens + PT1 00 [...]

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    Starter Kit Instruction Manual Description 19 4.4.4 Measuremen t connection These connections giv e access to the voltage on the laser. The ”L” connection is c onnected AC coupled to the catho de of the laser throug h a divider by ten. The end o f cable must be 50 Ω terminated for accu- rate measurement. The ”B” is co nnected the s ame to[...]

  • Página 21

    Starter Kit Instruction Manual Description 20 4.5 QCL pulser switc hing un it(LDD100) 4.5.1 Description The switching unit is based on dedicated p ow er MOS-FETS with up to 3 0A curre n t compatibilities and 60V. In addition, the circuit is limited in p ower dissipation b y the coo ling of t he unit. During op- eration, the temperature o f the case[...]

  • Página 22

    Starter Kit Instruction Manual Description 21 4.6 QCL pulse switc hing measuring u nit 4.6.1 Generalities The measur ing circuit contained in the LDD100 provides information ab out v ar ious laser pulse pa - rameters (pea k voltages, supply v oltages, duty cy- cle, frequency). They are o nly estimated v alues, since exa ct mea surement of short and[...]

  • Página 23

    Starter Kit Instruction Manual Description 22 Dut y cycle calculation UPI can b e used to calculate the duty factor a s follows: d f = 2 U P I − ν P low ν P high − ν P low with v P low and v P hig h as ab ov e. T o get the real dut y cyc le, df must be corre cted as follows: dc = f LDD d f = f LD D 2 U P I − ν P low ν P high − ν P low[...]

  • Página 24

    Starter Kit Instruction Manual Description 23 4.6.5 Laser p eak v oltage The la ser p eak voltage is given by: U peak = 2 U LH − U LL peak where U LL peak is the co rrected p eak v alue o f ULL as calculated in the previo us paragra ph. 4.6.6 Av erage dissipation The average thermal dissipa tion o f the laser is giv en by: P = U peak I peak dc wh[...]

  • Página 25

    Starter Kit Instruction Manual Description 24 4.7 QCL pulser timing unit (TPG128) 4.7.1 Description The QCL pulser timing unit is desig ned to control the QCL pulser switching unit. It provides TTL pulses on 50Ω o n tw o indep en- dent outpu ts. The pulse duratio n is adjustable from 0 to 200 ns. The interv al betw een pulses can b e ad- justed b[...]

  • Página 26

    Starter Kit Instruction Manual Description 25 4.8 QCL temp erature con troller(TCU15 1) 4.8.1 Description The TCU15 1 is us ed to con trol the laser’s temper- ature inside the Lab or atory Laser Housing. It uses a P T100 sensor to mea sure the temp era- ture of the cold plate and ma in tains a pre-set tem- per ature either from a fro n t panel kn[...]

  • Página 27

    Chapter 5 Installation 5.1 Chapter o v erview This chapter desc ribes the installation and the con- nection of the Q CL Starter Kit. It also explains the op erating checks before the normal use. 5.2 General The setup pro cedures outlined below m ust be fol- low e d meticulously to ensure that QCL Starter Kit op erates corr ectly and sa fely . 5.3 P[...]

  • Página 28

    Starter Kit Instruction Manual Installation 27 5.4 Setting the appropriate A C v oltage on TCU151 The TCU15 1 temp erature controller w orks on 110 /120V or 220/2 40V if the fuse holder is or ien ted in the ap- propriate p osition. Note: Ther e ar e two r ates: 110-120 V, 60Hz (USA) 220-240 V, 50Hz (Eur op e) 5.4.1 Pro cedure T o set the appropr ia[...]

  • Página 29

    Starter Kit Instruction Manual Installation 28 5.5 Installing the starter Kit 5.5.1 Before b eginning Make sure that the following devices are turned OFF: • TPG128 • TCU151 • User DC p ow er s upply 5.5.2 Pro cedure T o install the QCL Star ter Kit, pro ceed as fo llows: [1] Plug t he low impedance line in to the LLH100 connector (2). The lin[...]

  • Página 30

    Starter Kit Instruction Manual Installation 29 [3] Plug the cable ( 3) onto the LDD100(4). [4] Plug the +12VDC co nnector (1) in to the TPG128 (9). [5] Plug the trig ger BNC co nnector (2) into the T PG128 (9) Out 1 or Out 2 outptut. CAUTION ! The u nit must b e flo ating. [6] Plug the banana cables (8) (red a nd black) int o the DC p ower supply [...]

  • Página 31

    Chapter 6 Use 6.1 Chapter o v erview This chapter describ es how to use the QCL Starter Kit. It also explains the functionalities of the TPG12 8 and the T emp erature Co n troller (TCU151 ). 6.2 QCL pulse timing unit com- mand description The Quantum Cascade La ser is c ontrolled b y the QCL pulse timing unit TPG1 28. The TPG128 fro nt panel is c o[...]

  • Página 32

    Starter Kit Instruction Manual Use 31 6.3 TCU151 command description The in ternal temp erature of the LLH100 is driven by t he TCU15 1 unit. The T emper ature Controler front and rear pan- els are comp osed o f the following items: (1) Set T emperature 5 turns p otentiometer: Allows to set the internal temper ature refer- ence. (2) LCD 3 dig its d[...]

  • Página 33

    Starter Kit Instruction Manual Use 32 6.4 Laser utilisat ion 6.4.1 Ov erview In order to insure a c orrect use and and an appropr i- ate lifetime to the laser, it is recommended to pro - ceed accor ding a sp ecific o rder as b elow: • Start water flo w to co ol the LLH10 0. • T urn on the temperature controller and set the desired temp eratur[...]

  • Página 34

    Starter Kit Instruction Manual Use 33 [5] T urn the TPG128 ON (8) and set the pulse per io d to 2.0 and the range to 0.5 to 10.5 µ s (medium), cor resp onding to a perio d length of ab out 2.5us, or to the v alues sp ecified o n the datasheet or by Alpes L asers. [6] Set the pulse duration (11 ) to 3.0, corre- spo nding to a pulse length of about[...]

  • Página 35

    Starter Kit Instruction Manual Use 34 6.5 In terlo ck util isation The temper ature controller is designed with an built- in in terlo ck (1). This function is activ ated when a fault o ccurs o n the TCU1 51 controller (ov er -temper ature, ov er-current, etc.). The in terlo ck is b y default a NC (Normally Close) relay con tact. CAUTION ! It is als[...]

  • Página 36

    Chapter 7 T roublesho oting 7.1 Chapter o v erview This chapter sets out troublesho oting instructions for ensur ing safe and tro uble-free op era tion of the Quantum Cascade Laser Starter Kit sys tem. 7.2 Principle The p erso nnel must hav e read a nd understo o d this do cumen tation b efore carrying o ut any activity what- so ever with the Q uan[...]

  • Página 37

    Starter Kit Instruction Manual T roubleshoo ting 36 Laser dra ws curren t but giv es no ligh t - The laser ma y b e reversed pol arized (it is not a desirable situation but do es gen- erally not des tro y the laser). √ Check th e p olar it y of the connection. - The p olarity is righ t. It dra ws to o muc h curren t and the p ow er meter i s misa[...]

  • Página 38

    Chapter 8 Main tenance 8.1 Ov erview This chapter describes a ll pro cedures of mainte- nance and ca libration for the Q CL starter Kit. The pro cedures describ ed here in must be performed by per sonnel trained o n the electronic field, with a c- ceptance by Alpes Lasers , otherwise the w arrant y will be lo st. Note: The TTL Pulse Gener ator (TP[...]

  • Página 39

    Starter Kit Instruction Manual Maintenance 38 8.2 Replacemen t pro cedur es 8.2.1 Quan tum Cascade Las er replace- men t Before b eginning [1] Switch the QCL Starter Kit OFF Material needed • 1 set of Allen keys. • 1 ohmmeter. • 1 QCL laser. • a pair o f t weezers. Pro cedure T o replace the Quan tum Cascade La ser, pro ceed a s follows: [1[...]

  • Página 40

    Starter Kit Instruction Manual Maintenance 39 [4] Install the new laser ( 4) into the holder using small tw eezer s ( 0.5 cm ap erture). [5] Hold the laser (4) on the g ilded ceramic pads with the t weezers pins alo ng the axis o f the largest length of t he copp er submount . [6] Pla ce it in the r eceptacle para llel to the window. ! W arning ! A[...]

  • Página 41

    Starter Kit Instruction Manual Maintenance 40 8.2.2 QCL ”UP” and ”DN ” p osition exc hange Before b eginning [1] Switch the QCL Starter Kit OFF. Material needed • 1 set of Allen keys. • 1 ohmmeter. • 1 FP-Q CL laser co nt act pla te. • 1 pair o f t weezers. Pro cedure T o exchange the b eam of a Quantum Cascade Laser , pro ceed as f[...]

  • Página 42

    Starter Kit Instruction Manual Maintenance 41 [5] Place the screws (3) in the PET ho lder (4). [6] Place the PET holder (4) on the t wo guides (5) on the bac k of the laser receptacle ( 6) being ca reful of maintaining t he PET holder higher on the laser side than on the back side. [7] Once the holder (4) is eng aged in the guides, push it down unt[...]

  • Página 43

    Starter Kit Instruction Manual Maintenance 42 8.3 TCU151 temp erature con- troller in terlo c k setting 8.3.1 Generalities The interlock is lo cated on the ma in b oard. Note: By default, the interlo ck is set to NC (Nor- mal ly Close) c ontact. 8.3.2 Before b eggining in terlo ck set- ting [1] Switch the instrument OFF. [2] Unplug the p ow er cord[...]

  • Página 44

    Starter Kit Instruction Manual Maintenance 43 8.4 Calibarati on pro c edures 8.4.1 TPG128 calibration Generalities The present section descr ibes pro cedure to b e car- ried out for par ticular calibration o f the TPG12 8. Before b eginning [1] Switch the instrument OFF. [2] Remov e the cov er (1). [3] Switch the instrument ON. ! W A RNING ! Keep i[...]

  • Página 45

    Starter Kit Instruction Manual Maintenance 44 [5] Cho ose the range 5 µ s to 105 µ s . Pot 10 turns Perio d on 10 . Adjust the adjustable capacitor max 105 µ s adj (4) in o rder to obtain a 1 05 µ s long p erio d. [6] Pot 10 turns Peri o d on 0. Ajust the pot Perio d min adj (1) in order to hav e a perio d of 5 µ s. [7] Repeat s teps 5) and 6)[...]

  • Página 46

    Starter Kit Instruction Manual Maintenance 45 [12] Connect os cilloscop e on the output Ou t1 . Load with a 5 0Ω . Cho os e a rep etition p erio d of ab out 5 µ s. [13] Pot 10 turns Dur ation on 10. Adjust capacitor Max dur ation (2) to hav e a output pulse of 2 00 ns +/- 5 ns. [14] Pot 10 turns Dur ation on 0 . Adjust the po t Out 0ns adj (1) i[...]

  • Página 47

    Starter Kit Instruction Manual Maintenance 46 8.4.2 TCU151 temp erature controller calibration ! W ARNING ! Keep i n mind that during the calibration pro cedure, the i nstrumen t is p o wered on. Before b eginning [1] Po wer off the instrument. [2] Op en the TCU151 top cover (1) to access the TCU151 ma in bo ard (2). Material needed • V o ltmete[...]

  • Página 48

    Starter Kit Instruction Manual Maintenance 47 Sensing level and range adjustemen t [4] Replace the ca ble connected to J8 (4) with the 100Ω 1% reference resisto r in the follow- ing wa y: Connect one side of the resisto rs to pins 1 and 2, the other s ide to pins 3 and 4 . [5] Measur e the voltage on Zn3/R10 (3). Note: The value should b e: - V =[...]

  • Página 49

    Starter Kit Instruction Manual Maintenance 48 T emp e rature Reference offset adjustment [10] Adjust B13 (3) to 0.000 with P3 (4) [11] Set t he temperature with th e Set T em- p er atur e p otent iometer (Fig.4 0 (7)) to +5 ◦ C , → The temp erature reference signal B13 should be ≥ 4 .3V [12] Set t he temperature with th e Set T em- p er atur[...]

  • Página 50

    Starter Kit Instruction Manual Maintenance 49 Oscillator chec k [15] Measure the freq uency on the pi n 7 of U13 (1). Note: The value is 28KHz + /- 3KHz Curren t/V oltage ratio adjustment [16] Adjust the trimmer P4 (6) in o rder to read B4 = 0 .6V (4). [17] Set the selector (5) to mo de S etting +I . The LCD scr e en should display 1.00 A . Note: I[...]

  • Página 51

    Starter Kit Instruction Manual Maintenance 50 CA UTION ! F or the further steps of this c hec k, l imit the pos itiv e cur ren t to 1 A and the negativ e one with 1.2 A b y means of the 5 turns p oten tiometer) T emp e rature lim it threshold [21] Measure the voltage on pin 2 of U10 (1). Note: The value should b e: 0.7V (= 70 ◦ C) (If ne e de d, [...]

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    Starter Kit Instruction Manual Maintenance 51 Curren t adjustmen t [28] Set the selecto r (3) to mo de Setting ◦ C and adjust the temp erature v alue to 25 ◦ C by m eans o f the Set T emp er atur e 5 tuns po rtent iometer P8 (2). [29] On the external power supply , rise slowly the v oltage to 30 V and the curr en t to 1.5 A. , → The tension s[...]

  • Página 53

    Starter Kit Instruction Manual Maintenance 52 Miscellaneous functions testing T emp e rature limit tes ting [37] Decrea se the temp erature limit threshold from 0.7 V to 0.3 V. Note: F or mor e details, se e T emp er atur e li mit thr eshold on p age 50. [38] Increase the temperature refere nce to 35 ◦ C. , → When the thr eshold is overp asse d[...]

  • Página 54

    Chapter 9 Application notes 9.1 Detection te c hniques 9.1.1 Direct absorption In a direct absorption mea surement, the change in int ensity of a beam is recorded as the latter crosses a sa mpling cell where the chemical to b e detected is contained. This measurement tec hnique has the adv antage of simplicity . In a version of this technique, the [...]

  • Página 55

    Starter Kit Instruction Manual Maintenance 54 9.1.3 Photoacoustic detection In the photoacoustic detection, the optical b eam is per io dically modulated in amplitude before illumi- nating the cell containing the absorbing c hemical. The expansio n generated by the p erio dic heating of the chemical creates an aco ustic wa ve whic h is detected by [...]

  • Página 56

    Chapter 10 App endix 10.1 Bias Circut (”Bias-T”) 10.1.1 General The Bia s-T allows to a pply a constant (DC) cur- rent to the laser in addition to the pulsed current (therefore a B ias-T is useless in CW mo de). The current is drawn from the e xternal (user supplied) power supply through the laser. This cur rent can be co n trolled electrica ll[...]

  • Página 57

    Starter Kit Instruction Manual Appendix 56 10.1.3 Specifications Bias frequency . . . . . . . . . . . . . . . . Up to 1 00 Hz Ach iev a ble shift . . . . . . . . . . . . . . . . . . . . . . . . 0 .1% Input voltage U in . . . . . . . . . . . . . . . . . . . 0 to 3 V Input v oltage threshold . . . . . . . . . . . . . . . . 0.6 V Input frequency F in[...]

  • Página 58

    Starter Kit Instruction Manual Appendix 57 Dangers and dis adv an tages o f using a Bi as-T circuit • Since a Bias-T only allows to heat the laser, the emissio n wav elength can only b e increa sed (or emission wa ven umber decrea sed), and out- put p ow er will decre ase with incr eased Bias current, due to the additional heating. This means tha[...]

  • Página 59

    Starter Kit Instruction Manual Appendix 58 • As a rule of thum b, the ov erall dissipated power (sum of DC Bias current dissipation and pulse current dissipation) must never be higher than the average dissipated p ower given b y the hig h- est current / voltage / temper ature combina- tion sp ecified in the datasheet. T ak e into account that th[...]

  • Página 60

    Starter Kit Instruction Manual Appendix 59 10.2 Unpac king NS laser from its transp ortation b o x Fig.54: Unpac king i nstructions for NS submounts[...]