Thorlabs Exlus-hd1 User manual

SPATIAL LIGHT MODULATORS

Applications

Wavefront Correction

Optical Trapping

Beam Steering

Pulse Shaping

Adaptive Optics

Holography

Laser Processing

Lithography

Click to Enlarge

Each Exulus SLM features multiple 8-

32 (M4) taps for post mounting. For a

list of items used in this setup, see the

App Note

tab.

Click to Enlarge

The Exulus SLMs (excluding the high-

power SLMs) are provided with a

magnetic cover; when the SLM is in

use, the cover can be attached to the

designated area on the housing (sides

for the HD1 models and back for the

Features

Liquid Crystal on Silicon (LCoS) with Reflective Coating

Panel Resolutions: 1920 x 1080 or 1920 x 1200

Operating Wavelengths: 400 - 850 nm, 650 - 1100 nm, or

1550 nm

High-Power Models Available for 400 - 850 nm or 650 - 1100 nm Operating Ranges

All-in-One and Separate-Panel Mounting Configurations

Liquid Cooling Module Included on SLM Head

Fill Factor: >90% (Varies by Model)

Independent Horizontal and Vertical SLM Panel Tilt Adjustments (Standard SLM

Models Only)

Trigger Output for Timing Control of Other Devices (All Models Except

EXULUS-HD1)

Fast Frame/Refresh Rates up to 180 Hz (EXULUS-HD1 Only, Using

Frame Boost)

Customizations Available:

Panel and Controller in Separate Units (Standard SLM Models

Only)

Other Retardance Ranges (Contact Tech Support for Details)

Thorlabs' Exulus® Spatial Light Modulators (SLMs) employ Liquid Crystal on

Silicon (LCoS) technology to produce high-resolution, high-speed reflective

phase modulation with individually addressable pixels. This phase control is

OVER VIEW

Reflective 2D Phase Only Spatial Light Modulators (SLMs)

400 - 850 nm, 650 - 1100 nm, or 1550 nm Operating Wavelengths

Available Resolutions: 1920 x 1080 or 1920 x 1200

Highly Stable Phase Control with Minimal Flickering

►

EXULUS-HD3HP

Removable SLM Head,

1920 x 1200 (WUXGA),

650 - 1100 nm

Image Generated by SLM Using Computer-

Generated Hologram Projection. For Details, See

EXULUS-HD1

1920 x 1080 (Full HD),

400 - 850 nm

EXULUS-HD1 - November 22, 2023

Item EXULUS-HD1 was discontinued on November 22, 2023. For informational purposes, this is a copy of

the website content at that time and is valid only for the stated product.

HD2, HD3, and HD4 models).

Video Insight: Calibrate a Spatial Light Modulator (SLM) for Phase Delay

Watch a demonstration of an interferometric method for calibrating the phase delay of reflective SLMs.

Key Specificationsa

Item #

Suffix

Operating

Wavelength

Panel

Resolution

Fill

Factor

Phase / Retardance

Rangeb

Frame

Rate

Output

Trigger

Liquid Cooling

Module

Separable SLM

Panel

HD1 400 - 850 nm 1920 x 1080

(Full HD) >93% 2π at 633 nm (Standard)

4.7π at 532 nm (Extended)

60 Hz or

180 HzcN/A - -

HD2 400 - 850 nm 1920 x 1200

(WUXGA) >92% π or 2π at 633 nmd60 Hz

Yes

(SMA)

- -

HD3 650 - 1100 nm 1920 x 1200

(WUXGA) >92% π or 2π at 1064 nmd60 Hz - -

HD4 1550 nm 1920 x 1200

(WUXGA) >92% π or 2π at 1550 nmd60 Hz - -

HD2HP 400 - 850 nm 1920 x 1200

(WUXGA) >92% π or 2π at 633 nmd,e 60 Hz

HD3HP 650 - 1100 nm 1920 x 1200

(WUXGA) >92% π or 2π at 1064 nmd,e 60 Hz

Complete specifications may be found on the Specs tab.

highly stable with minimal fluctuations and minimal crosstalk with adjacent

pixels. For maximum phase shift values, refer to the

table to the upper right. These spatial light modulators

provide far more pixels than lower-order phase

modulators such as segmented or deformable mirrors.

For applications requiring improved thermal stability

and high-power handling (≤200 W/cm) in the 400 nm to

850 nm or 650 nm to 1100 nm wavelength ranges, high-power SLMs are available.

Exulus spatial light modulators are driven by an input video signal and operate as a general Full HD or WUXGA. They are bundled with a software GUI that

provides complete control over the device. Different driving modes are supported by the software, including full frame, image input, video input, Fresnel lens,

diffraction, and computer-generated holography (CGH). The CGH mode also allows tilting and focusing effects to be overlaid onto a pattern. The GUI enables

quick switching between operating modes, as well as allowing images, videos, and patterns to be uploaded to the panel. For more details on the operating

modes, please see the Software and App Note tabs.

Standard Models

Each standard spatial light modulator (EXULUS-HD1, -HD2, -HD3, and -HD4) includes a built-in SLM panel with independent horizontal and vertical tilt

adjustment of ±3.2°. Locking rings are installed to fix the adjustment settings, as well as provide extra stability. Customized versions are also available with the

panel separated from the control unit; contact Tech Support for details.

These Exulus spatial light modulators have input ports compatible with HDMI* connectors and ship with two corresponding cables: one for connecting to an

HDMI-compatible output, and one for connecting to a DisplayPort*-compatible output. Also included are a mini-USB cable for connecting to a PC, a power supply

with a location-specific power cord and a HKTS-5/64 hex key thumbscrew for adjusting the horizontal and vertical tilt adjusters.

High-Power Models

Each high-power SLM (EXULUS-HD2HP and EXULUS-HD3HP) features a liquid-cooled SLM head and adapter board, which can be mounted directly on the

controller or positioned separately from the main housing. The SLM head includes two preinstalled 1/4" hoses with CPC®† valved quick-connect coupling inserts

for easy connection to a chiller, and the adapter board houses the FPC connectors and a circuit board that connects the controller and SLM head. We

recommend using Thorlabs' LK220 chiller (sold below) for full compatibility with the Thorlabs EXULUS software package.

These high-power spatial light modulators have input ports compatible with HDMI* connectors and ship with two corresponding cables: one for connecting to an

HDMI-compatible output, and one for connecting to a DisplayPort*-compatible output. A mini-USB cable is also included for connecting to a PC. To aid in

connecting to a liquid chiller, two CPC valved quick-connection fittings for both 4.3 mm (0.17") and 6.0 mm (0.24") inner diameter hoses are included with the

unit, as well a 2.5 mm stereo cable for thermistor compatibility. A power supply with a location-specific power cord, a USB drive with the software and manual,

and a BD-2M 2 mm balldriver for removing the adapter board and SLM head from the main unit are also shipped with these Exulus models.

*HDMI is a trademark or registered trademark of HDMI Licensing Administrator, Inc. DisplayPort is a trademark owned by the Video Electronics Standards

Association (VESA) in the United States and other countries. The use of such trademarks by Thorlabs does not constitute or imply any affiliation with or

endorsement or sponsorship by their respective trademark owners.

†CPC® is a registered trademark of Colder Products Company.

Angles of incidence other than 0° will result in phase shifts that differ from the programmed pattern. Angles of up to 10° are possible without significantly

affecting performance.

Frame Boost Mode (referred to as Triple Mode in the software) plays the R, G, and B channels of the video signal in succession, for an overall frame rate

of 180 Hz.

These retardance ranges are achievable by setting the phase stroke mode to half wave or full wave in the software.

HD2HP and HD3HP phase/retardance range values are for 30 °C when used with the LK220 liquid chiller.

Item # EXULUS-HD1(/M)

Panel Resolution 1920 x 1080 (Full HD)

Type Liquid Crystal on Silicon (LCoS) with Reflective Coating

Operating Wavelength 400 - 850 nm

Panel Active Area 12.5 mm x 7.1 mm

Pixel Pitch 6.4 µm

Fill Factor >93%

Reflective Coating Aluminum

Average Reflectance 75% (Typical)

Phase / Retardance Range 2π at 633 nm (Standard Mode); 4.7π at 532 nm (Extended Mode)

Angle of Incidencea0°

Optic Axis 45°

Reflected Wavefront Distortion <λ/7 @ 633 nm

Damage Threshold

CWb5 W/cm (532 nm, Ø0.0107 mm)

Pulsed (ns) 0.63 J/cm2 (532 nm, 8.6 ns, 10 Hz, Ø203 µm)

Pulsed (fs) 0.138 J/cm2 (535 nm, 59.4 fs, 100 Hz, Ø188 µm)

Frame Rate 60 Hz (Standard Mode); 180 Hz (Frame Boost/Triplec)

Fluctuation / Flickering (RMS)d<1% (Standard Mode); <5% (Extended Mode)

Beam Deviation Using Panel Tip / Tilt ±3.2°

Trigger OutputeNone

Trigger Output High Voltage Level N/A

Trigger Output Pulse Width N/A

Dimensions (L x W x H)f172.0 mm x 110.0 mm x 81.6 mm (6.77" x 4.33" x 3.21")

Weight 1.24 kg (2.73 lbs)

Storage Temperature 0 °C to 60 °C (32 °F to 140 °F)

Operating Temperatureg10 °C to 40 °C (50 °F to 104 °F)

PC Connection HDMI-Compatible Connector

USB 2.0 Connector

Bit Depth 8 Bit, 0 - 255 Gray Level

Other angles of incidence will result in phase shifts that differ from the programmed pattern. Angles of

up to 10° are possible without significantly affecting performance.

The power density of your beam should be calculated in terms of W/cm. For an explanation of why the

linear power density provides the best metric for long pulse and CW sources, please see the Damage

Thresholds tab.

Frame Boost Mode (referred to as Triple Mode in the software) plays the R,G, and B channels of the

video signal in succession, for an overall frame rate of 180 Hz.

Fluctuation / Flickering is the phase fluctuation as the percentage of the entire phase range and is

dependent on current phase setting. The value stated is the maximum fluctuation and typically occurs at

half of the phase range.

For more details on the external trigger output, please refer to the product manuals accessible through

the red Docs ( ) icons below.

The reported height dimension includes the maximum travel range of the adjuster knob.

SPECS

Ambient temperature fluctuations may cause the characteristics of your SLM to change. Using it at an

ambient temperature of 25 °C is recommended.

Item # EXULUS-HD2 EXULUS-HD3 EXULUS-HD4

Panel Resolution 1920 x 1200 (WUXGA)

Type Liquid Crystal on Silicon (LCoS) with Reflective Coating

Operating Wavelength 400 - 850 nm 650 - 1100 nm 1550 nm

Panel Active Area 15.42 mm x 9.66 mm

Pixel Pitch 8 µm

Fill Factor >92%

Reflective Coating Aluminum Dielectric

Average Reflectance 80% (Typical) 82% (Typical)

Phase / Retardance Range 2π at 633 nm (Full Wave Mode)

π at 633 nm (Half Wave Mode)

2π at 1064 nm (Full Wave Mode)

π at 1064 nm (Half Wave Mode)

2π at 1550 nm (Full Wave Mode)

π at 1550 nm (Half Wave Mode)

Angle of Incidencea0°

Optic Axis 0°

Reflected Wavefront Distortion <λ/2 @ 633 nm <0.4λ @ 633 nm

Damage Threshold

Pulsed (ns) 0.22 J/cm2

(532 nm, 6.8 ns, 10 Hz, Ø200.5 µm)

0.15 J/cm2

(1064 nm, 10 ns, 100 Hz, Ø235 µm)

0.187 J/cm2

(1550 nm, 6.0 ns, 10 Hz, Ø230.6 µm)

Pulsed (fs) 0.0935 J/cm2

(515 nm, 203.3 fs, 100 Hz, Ø108.2 µm)

0.03 J/cm2

(1030 nm, 200 fs, 100 Hz, Ø135 µm)

0.076 J/cm2

(1550 nm, 55.6 fs, 100 Hz, Ø143.1 µm)

Frame Rate 60 Hz

Fluctuation / Flickering (RMS)b<0.01% <0.05% <0.15%

Beam Deviation Using Panel Tip / Tilt ±3.2°

Trigger OutputcSMA Female

Trigger Output High Voltage Level 5 V (TTL)

Trigger Output Pulse Width 54 µs

Dimensions (L x W x H)d155.9 mm x 104.3 mm x 42.0 mm (6.14" x 4.11" x 1.65")

Weight 0.76 kg (1.68 lbs)

Storage Temperature 0 °C to 60 °C (32 °F to 140 °F)

Operating Temperaturee10 °C to 40 °C (50 °F to 104 °F)

PC Connection HDMI-Compatible Connector

USB 2.0 Connector

Bit Depth 8 Bit, 0 - 255 Gray Level

Other angles of incidence will result in phase shifts that differ from the programmed pattern. Angles of up to 10° are possible without significantly

affecting performance.

Fluctuation / Flickering is the phase fluctuation as the percentage of the entire phase range and is dependent on current phase setting. The value stated

is the maximum fluctuation and typically occurs at half of the phase range.

For more details on the external trigger output, please refer to the product manuals accessible through the red Docs ( ) icons below.

The reported length dimension includes the maximum travel range of the adjuster knob. The specified height does not include the dust cover; when

included, this dimension is nominally 46 mm.

Ambient temperature fluctuations may cause the characteristics of your SLM to change. Using it at an ambient temperature of 25 °C is recommended.

Item # EXULUS-HD2HP EXULUS-HD3HP

Panel Resolution 1920 x 1200 (WUXGA)

Type Liquid Crystal on Silicon (LCoS) with Reflective Coating

Operating Wavelength 400 - 850 nm 650 - 1100 nm

Panel Active Area 15.42 mm x 9.66 mm

Pixel Pitch 8 µm

Fill Factor >92%

Reflective Coating Aluminum

Average Reflectance 80% (Typical)

Phase / Retardance Rangea2π at 633 nm (Full Wave Mode)

π at 633 nm (Half Wave Mode)

2π at 1064 nm (Full Wave Mode)

π at 1064 nm (Half Wave Mode)

Angle of Incidenceb0°

Optic Axis 0°

Reflected Wavefront Distortion <λ/2 @ 633 nm <0.4λ @ 633 nm

Frame Rate 60 Hz

Optical Power Handlingc≤200 W/cm

Damage Threshold

Pulsed (ns) 0.22 J/cm2

(532 nm, 6.8 ns, 10 Hz, Ø200.5 µm)

0.15 J/cm2

(1064 nm, 10 ns, 100 Hz, Ø235

µm)

Pulsed (fs)

0.0935 J/cm2

(515 nm, 203.3 ns, 100 Hz, Ø108.2

µm)

0.03 J/cm2

(1030 nm, 200 fs, 100 Hz, Ø135

µm)

Fluctuation / Flickering (RMS)d<0.01% <0.15%

Beam Deviation Using Panel Tip /

Tilt N/A

Trigger OutputeSMA Female

Trigger Output High Voltage

Level 5 V (TTL)

Trigger Output Pulse Width 54 µs

Connector Type (for Tubing) CPC® Valved Thumb Latch Quick-Disconnect Fitting

Tubing Dimensions 0.17" (4.3 mm) Inner Diameter (Pre-Installed)

0.24" (6 mm) Inner Diameter (Optional)

Dimensions (L x W x H)

220.0 mm x 104.0 mm x 68.0 mm (8.66" x 4.09" x 2.68") All-in-One Mode

420.0 mm x 104.0 mm x 42.0 mm (16.54" x 4.09" x 1.65") Separate-

Panel Mode

Weight 0.7 kg (1.54 lbs)

Storage Temperature 0 °C to 60 °C (32 °F to 140 °F)

Operating Temperaturee10 °C to 40 °C (50 °F to 104 °F)

PC Connection HDMI-Compatible Connector

USB 2.0 Connector

Bit Depth 8 Bit, 0 - 255 Gray Level

SLM Head Thermistor

Type VISHAY NTC LE413 (R0 = 10 kΩ @ T0 = 25 °C, B = 3435 K)

Accuracy ±0.5 °C (@ 25 °C)

Phase/retardance range values are for 30 °C when used with the LK220 liquid chiller.

Other angles of incidence will result in phase shifts that differ from the programmed pattern. Angles of

up to 10° are possible without significantly affecting performance.

Specification with the LK220 Liquid Chiller

Fluctuation / Flickering is the phase fluctuation as the percentage of the entire phase range and is

dependent on current phase setting. The value stated is the maximum fluctuation and typically occurs at

half of the phase range.

For more details on the external trigger output, please refer to the product manuals accessible through

the red Docs ( ) icons below.

Ambient temperature fluctuations may cause the characteristics of your SLM to change. Using it at an

ambient temperature of 25 °C is recommended.

Diffraction Efficiency

DIFFRACTION EFFICIENCY

Phase Patterns Used to Measure Diffraction Efficiency

Click to Enlarge Click to Enlarge

When a repeating, linear phase pattern is displayed on the SLM, it will function similarly to a blazed diffraction grating. The diffraction efficiency is the power in

the first-order of the diffraction pattern divided by the zero-order when the phase of the SLM is set to zero across the panel. These measurements were made at

633 nm, 1064 nm, or 1550 nm for several test patterns with varying phase steps, effectively creating gratings with varying line spacing (denoted as line pair

/ mm). The measured results and patterns used are plotted below.

Click to Enlarge

Frame Tab in Standard Frame Rate Mode:

Setting a specific gray level from 0 to 255 will set

the entire panel to a certain phase level.

"Spatial Light Modulator" Software Package for EXULUS-HD1

Each Exulus® SLM comes with a software interface that provides complete control of the SLM panel as well as

device settings. Users can input a specific phase level (gray level) over the entire panel, import a custom image,

produce a computer generated holography (CGH) pattern, and other patterns such as Fresnel lenses and

diffraction gratings. All the patterns can be saved into a sequence list and played with a predefined interval of

16.7 ms (60 Hz frame rate, EXULUS-HD1, EXULUS-HD2, EXULUS-HD3, EXULUS-HD4, EXULUS-HD2HP, and

EXULUS-HD3HP). The EXULUS-HD1 also features a triple mode; if RGB images are used then the RGB channels

will be played in succession for an overall frame rate of 180 Hz. The software also supports video input at 1080p or

4K resolution with the H.264 video codec (supported file formats: MP4, M4V, and MOV).

Note: There are two separate software packages for our Exulus spatial light modulators:

The "Spatial Light Modulator" software package is designed for use with our EXULUS-HD1.

The "Thorlabs EXULUS" software package is designed for use with our EXULUS-HD2, EXULUS-HD3,

EXULUS-HD4, EXULUS-HD2HP, and EXULUS-HD3HP SLMs.

Click the yellow bars below for screenshots highlighting various software features and capabilities:

SOFTWARE

Software

"Spatial Light Modulator" Software

Version 1.0.12

This software package is designed for use

with our EXULUS-HD1 SLMs.

"Thorlabs EXULUS" Software Version

2.5.1

This software package is designed for use

with our EXULUS-HD2, EXULUS-HD3,

EXULUS-HD4, EXULUS-HD2HP, and

EXULUS-HD3HP SLMs.

Click the button below to visit the software

page.

Click to Enlarge

Frame Tab in Triple Frame Rate Mode (EXULUS-HD1):

Each of three successive frames (at 180 fps) can have a

different gray level.

Click to Enlarge

File Tab: Upload a user-defined pattern in PNG,

JPEG, or BMP format.

Click to Enlarge

CGH Tab: Convert a user-defined image into a

holographic pattern. For more details, please see

the

App Note

tab.

Click to Enlarge

Pattern Tab for Fresnel Lens Generation: Sets

the SLM panel to focus the reflected light at a

user-selected wavelength and focal length.

Click to Enlarge

Pattern Tab for Diffraction Grating Generation:

Sets the SLM panel to diffract the reflected light with

user-selected wavelength, deviation angle, and

grating rotation angle. For more infromation about

the diffraction efficiency of different patterns, please

see the

Specs

tab.

Click to Enlarge

Video Tab: User-uploaded video can be played on

the SLM panel. In standard mode, grayscale video

can be played at a 60 Hz (EXULUS-HD1, EXULUS-

HD2, and EXULUS-HD4) frame rate. In triple mode

(EXULUS-HD1 only), a color video will play the R,

G, B channels in succession at a 180 Hz frame

rate.

Click to Enlarge

Frame Tab in Standard Frame Rate Mode:

Click to Enlarge

File Tab: Upload a user-defined pattern in PNG,

"Thorlabs EXULUS" Software Package for EXULUS-HD2, EXULUS-HD3, EXULUS-HD4,

EXULUS-HD2HP, and EXULUS-HD3HP

Setting a specific gray level from 0 to 255 will set

the entire panel to a certain phase level.

JPEG, or BMP format.

Click to Enlarge

CGH Tab: Convert a user-defined image into a

holographic pattern. For more details, please see

the

App Note

tab.

Click to Enlarge

Pattern Tab for Fresnel Lens Generation: Sets

the SLM panel to focus the reflected light at a

user-selected wavelength and focal length.

Click to Enlarge

Pattern Tab for Diffraction Grating Generation:

Sets the SLM panel to diffract the reflected light with

user-selected wavelength, deviation angle, and

grating rotation angle. For more infromation about

the diffraction efficiency of different patterns, please

see the

Diffraction Efficiency

tab.

Click to Enlarge

Pattern Tab for Vortex Generation: This

pattern creates a helical output beam and contains

a characteristic donut beam profile. The mode

contains two parameters: wavelength and pattern

order m.

Click to Enlarge

Pattern Tab for Cubic Phase Generation: This

pattern generates a non-diffracted beam with self-

recovery characteristics, commonly called an airy

beam. The mode contains two parameters:

wavelength and alpha.

Click to Enlarge

Sensor Setting: When a high-power SLM is

connected to the LK220 chiller, the temperature

sensor can be set to internal or external mode. The

internal sensor measures the output coolant

temperature, while the external sensor gives the

thermistor temperature reading from the LK220

chiller.

Polarization Dependence of Phase-Only Spatial Light

Modulators (SLMs)

The optical working principles of liquid crystal on silicon SLMs that

provide phase-modulated output beams are illustrated.

Click to Enlarge

Figure 1: A schematic diagram of the SLM LCoS

panel.

Overview

Two-

dimensional

spatial light

modulators

(SLMs) offer

individually

addressable

pixels of phase

shift. Thorlabs' Exulus® 2D SLM is fabricated with liquid crystal on silicon (LCoS) technology, which is based on display technology. This allows it to provide far

more pixels than lower-order phase modulators such as segmented or deformable mirrors. Also, the phase shift of one pixel has little crosstalk with other pixels.

Therefore, the Exulus 2D SLM is perfect for many beam manipulation applications including optical trapping, beam steering and shaping, femtosecond pulse

shaping, adaptive optics, imaging applications, and holography.

APP NOTE

Click to Enlarge

Figure 2: Setup for CGH using the EXULUS-HD1 SLM. In this case, the

focusing effect added to the CGH is set to a 100 000 mm focal length.

[APPLIST] [APPLIST]

These product lists do not include the optical breadboard, laptop, or

screws used to mount the post holders to the breadboard.

Click to Enlarge

Figure 4: CGH projection of an image using the setup

shown in Figure 2 and the image shown in Figure 3.

The central bright spot is a zero-order diffraction spot

due to the gaps between the SLM pixels.

Click for Full-Resolution Example Image

Click to Enlarge

Figure 3: a. The image used to generate the holographic projection.

b. The corresponding CGH pattern generated by the Exulus software.

The main component of the Exulus® is the 2D SLM LCoS panel. Figure 1 shows a basic schematic of the LCoS panel. The liquid crystal layer is sandwiched

between the top transparent and conductive ITO electrode, and the reflective electrode on the bottom. Each pixel on the SLM panel corresponds to individually

addressable electrodes on the bottom. Together with the ITO layer on top, an electric field is built up by applying a voltage between the two electrodes. The liquid

crystal modules line up according to the direction and strength of the electric field. Since liquid crystal is a birefringent material, the alignment of the liquid crystal

molecules in turn controls the retardance or phase shift of each pixel. A wavefront that is incident on the panel reflects with its phase or wavefront being shifted

according to the signal that is sent to the SLM panel. With a properly calculated pattern on the SLM panel, the reflected wavefront results in different optical

effects in the far field. These effects typically include diffraction, tilt, focus, and holographic image formation.

Holographic Projection

We show here a holographic projection as one of the applications of the Exulus SLM.

Figure 2 shows a typical setup required to realize a 2D holographic projection using the

EXULUS-HD1. A collimated laser beam is incident on the SLM panel; best results for

holographic projection are obtained using a beam size just smaller than Ø7 mm. The

incident beam passes through a polarizer and a half-wave plate such that it is polarized

at 45°, the direction of the optical axis of the panel. The target projection image is first

converted into a computer generated holography (CGH) pattern that is calculated by

the bundled software (accessed through the CGH tab in the software). The output

beam is separated from the incident beam with a beam splitter. Within the SLM

software, a focusing effect is added to the CGH pattern; if you do not desire to have

the SLM provide focusing, set the focal length to an extremely long value. In this

example, we have set the focal length to 100 000 mm (at the laser wavelength of 635 nm), checked the "Invert Image" box to set the image outline to be bright in

the projected pattern, and set the position to "Fit" so that the entire image is visible on the preview. Since CGH relies on far-field diffraction, a set of imaging

lenses is required to produce a sharp holographic image on a screen (in this example, first lens: f = 50 mm, second lens: f = 75 mm). Figure 3 shows the

holographic image to be projected and the corresponding CGH pattern, which is calculated using the bundled software. The resulting holographic projection is

shown in Figure 4.

c. The CGH settings tab in the Exulus software.

Table of contents

Other THORLABS Modulator manuals