HomeProductsApplicationsEducational Kits Portable Optical Tweezers Kit

Portable Optical Tweezers Kit


Portable Optical Tweezers Educational Kit

  • Designed for Education,Demonstration, and Classroom Use
  • Easy-to-Use Kit Includes All Component Plus Educational Materials

Optical Tweezers Educational Kit

  • Designed for Educational, Demonstration, and Classroom Use
  • Complete Kit Includes All Hardware and Tools (Computer Not Included)
  • Includes Extensive Manual for Easy Assembly and Use
  • Choose from Kits Containing Imperial or Metric Components

Kit Details

  • Optical Tweezers Kit
  • Portable without Readjustment
  • Visible Trapping Laser
  • Imperial or Metric Versions Available

Optical tweezers, also known as optical traps, move and manipulate small particles using only a beam of light. A focused laser beam is used to exert forces on electrically uncharged particles with sizes from 1 to 10 µm, allowing the particles to be trapped, moved, and manipulated. This optical tweezers kit is optimized for classroom and lab use. It features an easy-to-construct optical path and sample positioning stage, a visible laser source, and a camera system for easy demonstration. The kit is assembled on a 30 cm x 60 cm (1' x 2') aluminum optical breadboard (included) and can be easily moved for demonstration purposes without needing realignment.

Thorlabs Educational Products

Thorlabs' educational line of products aims to promote physics, optics, and photonics by covering many classic experiments, as well as emerging fields of research. Each kit includes all the necessary components and a manual that contains both detailed setup instructions and extensive teaching materials. These kits are being offered at the price of the included components, with the educational materials offered for free.


Thorlabs demonstration/educational optical tweezers kit is designed for classroom, lab, and other educational uses. It features a visible laser light source and an objective that does not require oil immersion. The CMOS viewing camera can be connected to a PC for demonstration use. The entire system is mounted on a 30 cm x 60 cm (1' x 2') aluminum breadboard and can be easily moved without needing realignment.

Laser and Microscope System

The EDU-OT1(/M) kit uses a L658P040 658 nm laser diode as the trap laser source. This 40 mW visible laser allows the spot to be easily observed through the microscope during operation for intuitive classroom demonstrations. The laser is focused through a Zeiss 63X, 0.8 NA objective, which also serves as the objective for the microscope. Sample illumination is accomplished using an MCWHL5 white LED, and the sample is viewed through a Thorlabs DCC1645C color CMOS camera. The laser, microscope, and optical path of the optical tweezers kit are shown below to the left.

Sample Positioning System

Samples are placed on the 3-axis sample positioning stage and moved around the static laser beam during experiments. The stage consists of two motorized MT1-Z8 (MT1/M-Z8) 12 mm travel translation stages for X- and Y-axis travel, plus a manual MT1 (MT1/M) stage for Z-axis translation. The motorized stages are controlled by TDC001 servo motor controllers, each of which features a 1-axis actuator with customizable velocity settings.



Several experiments that students can undertake as part of a lab course are outlined below. In addition to these exercises, the manual contains instructions for more activities such as adjusting the setup, finding the correct focus plane for the camera and laser, and arranging trapped particles within a sample.

Sample Preparation

Samples for the optical tweers kit are simple to prepare. A sample containing 1 µm or 3 µm polystyrene beads is useful, as these are well-suited for getting to know the operation and handling of the optical tweezers. Alternatively, an emulsion of cream in water will also produce particles that can be captured with the optical tweezers kit.

The following materials are necessary to create the sample:

  • Microscope Slide with 20 µm Deep Wells
  • Cover Glass
  • Watch Glass Dish
  • Pipette
  • Sample Solution:
    • Solution with Polystyrene Beads (PS) and Distilled Water
    • Cream and Water Emulsion

First, place a drop of the solution with the PS beads in the watch glass dish and combine with sufficient distilled water. Place this mixture in a well on the microscope slide using a pipette. Put a cover glass over the sample so that there are no air bubbles between the glass and the sample.

The samples can either be prepared before each experiment or they can be sealed between the slide and the coverglass with a UV adhesive. We recommend allowing students to prepare new samples as an educational exercise.

Manipulation of a Cream Particle within a Cream Water Emulsion

Particles of dairy cream in a cream water emulsion are an appropriate size to be trapped by the optical tweezers in this kit. A sample can be created by mixing a drop of dairy cream with enough water to create a solution that is slightly milky in appearance. If one attempts to trap the cream particles with the laser, they will disappear from the focus and can no longer be clearly seen on the monitor (see the image to the right).  The observation can be explained by the composition of the cream/water emulsion.  Cream consists primarily of fat, which collects on the surface when mixed with water.  The cream particles are therefore located on the surface of the water.  However, the laser focus is located at a deeper level: when the cream particles are trapped, they are pulled down into the emulsion.  This effect can be observed when the particle at which the laser is directed is tracked by adjusting the height of the stage as the particle moves deeper into the solution.

After the cream particle located in the optical trap has been brought into focus and thus can clearly be seen on the monitor, the laser can be switched off and the particle observed.  Since the cream particle is not held in place by an optical trap after the laser is switched off, it will move upward once again to the surface of the water.  Again, the motion of the particle can be tracked by adjusting the height of the stage.



Our Mission is to accelerate the advancement of optical technology for precision measurements and their applications from the table tops of research laboratories to standard use in communication and high technology industries. Our aim is to serve our customers. Our hope is to create a place for highly skilled people in an open environment

contact us

Tel               +966 35823441
Fax               +966 35823441
Egypt Mobile  +2 0120 7577664
KSA Mobile     +966 545 991188
Email             This email address is being protected from spambots. You need JavaScript enabled to view it.