• Visit
    • Calendar
    • After Dark Thursdays
    • Buy Tickets
    • Exhibits
    • Museum Galleries
    • Artworks on View
    • Hours
    • Getting Here
    • Visitor FAQ
    • Event Rentals
    • Field Trips
  • Education
    • Professional Development Programs
    • Free Educator Workshops
    • Tools for Teaching and Learning
    • Learning About Learning
    • Community Programs
    • Educator Newsletter
  • Explore
    • Browse by Subject
    • Activities
    • Video
    • Exhibits
    • Apps
    • Blogs
    • Websites
  • About Us
    • Our Story
    • Partnerships
    • Global Collaborations
    • Explore Our Reach
    • Arts at the Exploratorium
    • Contact Us
  • Join + Support
    • Donate Today!
    • Membership
    • Join Our Donor Community
    • Engage Your Business
    • Attend a Fundraiser
    • Explore Our Reach
    • Thank You to Our Supporters
    • Donor & Corporate Member FAQ
    • Host Your Event
    • Volunteer
  • Store
  • Visit
    • Frequently Asked Questions
    • Calendar
      • Today
      • This Week
      • Online
      • After Dark Thursday Nights
      • Arts
      • Conferences
      • Cinema Arts
      • Free + Community Events
      • Fundraising Events
      • Kids + Families
      • Members
      • Special Hours
      • Private Event Closures
    • Prices
    • Hours
    • Getting Here
    • Museum Map
    • Free Admission and Reduced Admission
    • Accessibility
    • Tips for Visiting with Kids
    • How to Exploratorium
    • Exhibits
    • Tactile Dome
    • Artworks on View
    • Cinema Arts
    • Kanbar Forum
    • Black Box
    • Museum Galleries
      • Bernard and Barbro Osher Gallery 1: Human Phenomena
        • Tactile Dome
          • 1971 Press Release
        • Black Box
        • Curator Statement
      • Gallery 2: Tinkering
        • Curator Statement
      • Bechtel Gallery 3: Seeing & Reflections
        • Curator Statement
      • Gordon and Betty Moore Gallery 4: Living Systems
        • Curator Statement
      • Gallery 5: Outdoor Exhibits
        • Curator Statement
      • Fisher Bay Observatory Gallery 6: Observing Landscapes
        • Wired Pier Environmental Field Station
        • Curator Statement
    • Restaurant & Café
    • School Field Trips
      • Getting Here
        • Bus Routes for Field Trips and Other Groups
      • Admission and Tickets
      • Planning Guide
      • Reservations
        • Field Trip Request Form
      • Resources
    • Event Rentals
      • Full Facility & Gallery Bundles
      • Fisher Bay Observatory Gallery & Terrace
      • Moore East Gallery
      • Bechtel Central Gallery & Outdoor Gallery
      • Osher West Gallery
      • Kanbar Forum

      • Weddings
      • Proms and School Events
      • Daytime Meetings, Events, & Filmings

      • Rentals FAQ
      • Event Planning Resources
      • Rental Request Form
      • Download Brochure (pdf)
    • Groups / Tour Operators
      • Group Visit Request Form
    • Exploratorium Store
    • Contact Us
  • Education
    • Black Teachers and Students Matter
    • Professional Development Programs
      • Free Educator Workshops
      • Professional Learning Partnerships
      • Teacher Institute
        • About the Teacher Institute
        • Summer Institute for Teachers
        • Teacher Induction Program
        • Leadership Program
        • Teacher Institute Research
        • CA NGSS STEM Conferences
          • NGSS STEM Conference 2020
        • Science Snacks
          • Browse by Subject
          • Special Collections
          • Science Snacks A-Z
          • NGSS Planning Tools
          • Frequently Asked Questions
        • Digital Teaching Boxes
        • Meet the Teacher Institute Staff
        • Resources for Supporting Science Teachers
      • Institute for Inquiry
        • What Is Inquiry?
        • Watch and Do Science
        • Inquiry-based Science and English Language Development
          • Educators Guide
            • Conceptual Overview
              • Science Talk
              • Science Writing
            • Classroom Video Gallery
              • Magnet Investigation
              • Snail Investigation
            • Teacher Professional Development
            • Project Studies
            • Acknowledgments
          • Conference: Exploring Science and English Language Development
            • Interviews with Participants
            • Plenary Sessions
            • Synthesis, Documentation, and Resources
        • Workshops
          • Participant Portal
          • Fundamentals of Inquiry
            • Summary Schedule
          • BaySci Science Champions Academy
          • Facilitators Guides
          • Commissioned Workshops
        • Resource Library
        • Meet the IFI Staff
      • Resources for California Educators
      • K-12 Science Leader Network
      • Resources for Supporting Science Teachers
      • Field Trip Explainer Program
      • Cambio
    • Tools for Teaching and Learning
      • Learning Toolbox
      • Science Snacks
      • Digital Teaching Boxes
      • Science Activities
      • Tinkering Projects
      • Recursos gratuitos para aprender ciencias
      • Videos
      • Exhibits
      • Publications
      • Apps
      • Educator Newsletter
      • Exploratorium Websites
    • Educator Newsletter
    • Advancing Ideas about Learning
      • Visitor Research and Evaluation
        • What we do
        • Reports & Publications
        • Projects
        • Who we are
      • Center for Informal Learning in Schools
    • Community Programs
      • High School Explainer Program
      • Xtech
      • Community Educational Engagement
      • California Tinkering Afterschool Network
        • About
        • Partners
        • Resources
        • News & Updates
        • Further Reading
  • Explore
    • Browse by Subject
      • Arts
      • Astronomy & Space Sciences
        • Planetary Science
        • Space Exploration
      • Biology
        • Anatomy & Physiology
        • Ecology
        • Evolution
        • Genetics
        • Molecular & Cellular Biology
        • Neuroscience
      • Chemistry
        • Combining Matter
        • Food & Cooking
        • Materials & Matter
        • States of Matter
      • Data
        • Data Collection & Analysis
        • Modeling & Simulations
        • Visualization
      • Earth Science
        • Atmosphere
        • Geology
        • Oceans & Water
      • Engineering & Technology
        • Design & Tinkering
        • Real-World Problems & Solutions
      • Environmental Science
        • Global Systems & Cycles
        • Human Impacts
      • History
      • Mathematics
      • Nature of Science
        • Measurement
        • Science as a Process
        • Size & Scale
        • Time
      • Perception
        • Light, Color & Seeing
        • Listening & Hearing
        • Optical Illusions
        • Scent, Smell & Taste
        • Tactile & Touch
      • Physics
        • Electricity & Magnetism
        • Energy
        • Heat & Temperature
        • Light
        • Mechanics
        • Quantum
        • Sound
        • Waves
      • Social Science
        • Culture
        • Language
        • Psychology
        • Sociology
    • Browse by Content Type
      • Activities
      • Blogs
        • Spectrum
          • Arts
          • Behind the Scenes
          • News
          • Education
          • Community & Collaborations
          • Science
        • Eclipse
        • Studio for Public Spaces
        • Tangents
        • Resonance See & Hear Blog
        • Fabricated Realities
        • Tinkering Studio: Sketchpad
        • Exploratorium on Tumblr
      • Exhibits
      • Video
      • Websites
      • Apps
        • Total Solar Eclipse
  • About Us
    • Our Story
    • Land Acknowledgment
    • Explore Our Reach
    • Impact Report
    • Awards
    • Our History
      • 50 Years 1969–2019

    • Senior Leadership
    • Board of Trustees
    • Board of Trustees Alumni
    • Staff Scientists
    • Staff Artists

    • Arts at the Exploratorium
      • Artworks on View
      • Artist-in-Residence Program
      • Cinema Arts
        • History and Collection
        • Cinema Artists-in-Residence
        • Resources and Collaborating Organizations
        • Kanbar Forum
      • Center for Art & Inquiry
        • Begin Here
          • Lessons
            • Bob Miller/Light Walk
            • Ruth Asawa/Milk Carton Sculpture
          • Workshops
      • Resonance
        • About the Series
        • See & Hear
        • Past Seasons
      • Over the Water
      • Black Box
      • Upcoming Events
      • Temporary Exhibitions
      • Arts Program Staff
    • Teacher Institute
    • Institute for Inquiry
    • Explainer Programs
    • Studio for Public Spaces
    • Exhibit Making
    • Partnerships
      • Building Global Connections
        • Global Collaborations
          • Projects
          • Approach
          • People
          • Impact
      • Partnering with Science Agencies
        • NASA
        • NOAA
      • Partnering with Educational Institutions
      • Osher Fellows

    • Job Opportunities
    • Become a Volunteer

    • Contact Info
    • Newsletter
    • Educator Newsletter
    • Blogs
    • Follow & Share
    • Press Office

    • FY21 Audit Report
    • 990 FY20 Tax Return
    • Use Policy
      • Privacy Policy
      • Intellectual Property Policy
  • Join + Support
    • Donate Today!
    • Membership
      • Membership FAQ
      • Member Benefits
      • After Dark Membership
      • Member Events
      • May Is for Members
    • Join Our Donor Community
    • Engage Your Business
      • Corporate Membership
      • Luminary Partnerships
    • Attend a Fundraiser
      • Wonder Funday
      • Science of Cocktails
      • Party at the Piers
        • Event Leadership and Host Committee
    • Explore Our Reach
    • Thank You to Our Supporters
    • Donor & Corporate Member FAQ
    • Volunteer
      • How to Apply
      • Application for Internships
      • Our Contract
      • Application for Individuals
  • Press Office
    • Press Releases
    • News Coverage
    • Events Calendar
    • Photographs
    • Press Video
    • Press Kits
    • Press Visits
    • Exploratorium Logos
    • Recent Awards
    • Praise for the Exploratorium
    • Join Our Press List
  • Store

Masks and vaccinations are recommended. Plan your visit  

Visitor FAQ Buy Tickets Donate Today
Exploratorium
Exploratorium
  • Visit
    • Calendar
    • After Dark Thursdays
    • Buy Tickets
    • Exhibits
    • Museum Galleries
    • Artworks on View
    • Hours
    • Getting Here
    • Visitor FAQ
    • Event Rentals
    • Field Trips
  • Education
    • Professional Development Programs
    • Free Educator Workshops
    • Tools for Teaching and Learning
    • Learning About Learning
    • Community Programs
    • Educator Newsletter
  • Explore
    • Browse by Subject
    • Activities
    • Video
    • Exhibits
    • Apps
    • Blogs
    • Websites
  • About Us
    • Our Story
    • Partnerships
    • Global Collaborations
    • Explore Our Reach
    • Arts at the Exploratorium
    • Contact Us
  • Join + Support
    • Donate Today!
    • Membership
    • Join Our Donor Community
    • Engage Your Business
    • Attend a Fundraiser
    • Explore Our Reach
    • Thank You to Our Supporters
    • Donor & Corporate Member FAQ
    • Host Your Event
    • Volunteer
  • Store
Science Snacks
Science activity to convert your cell phone into a Miniscope
Science activity to convert your cell phone into a Miniscope
Science activity to convert your cell phone into a Miniscope
  • Science activity to convert your cell phone into a Miniscope
  • Science activity to convert your cell phone into a Miniscope
  • Science activity to convert your cell phone into a Miniscope

Cell Phone Miniscope

Use your cell phone to explore the mini-scopic world.

Open your eyes to the amazing world of the ultra-tiny when you convert your cell phone into a portable, picture-taking Miniscope using a simple plastic lens from a laser pointer.


Grade Bands: 
6-8
9-12
Subject: 
Biology
Nature of Science
Measurement
Size & Scale
Keywords: 
microscope
cell phone
lens
laser
video
NGSS and EP&Cs: 
LS
LS1
PS
PS4
ETS
ETS1
CCCs
Scale, Proportion, and Quantity

  • Facebook logo
  • Reddit logo
  • Twitter logo


Video Demonstration


Tools and Materials

  • Small piece of poster tack or removable adhesive putty
  • Laser-pointer lens—also known as a laser collimating lens—with a diameter of between 6 and 8 mm and a focal length as short as possible (that is, having as much curvature as possible); alternatively, you can remove the lens from an existing (preferably nonfunctioning) laser pointer
  • Cell phone with built-in camera
  • Interesting objects to look at
  • Optional: printout of this metric ruler (or similar ruler with millimeters marked) 
  • Optional: flashlight and partner

Assembly

  1. Turn on the cell phone, and put it in camera mode.
  2. Tear off a piece of poster tack about the size of a pea and roll it into a cylinder approximately 1 inch (2 to 3 cm) long.
  3. Wrap the poster tack around the circumference of the lens, as shown in the photo below. If it isn’t quite long enough to go all the way around, roll it out more to lengthen it and try again.

  4. Place the putty-wrapped lens on your fingertip, and bring it toward the camera lens on the back of your phone. You should see a dark circle on the phone’s screen (see left photo below). That circle is the outer edge of the laser pointer’s lens on your finger. Use the circle to center the laser-pointer lens as you bring it even closer to the cell phone (see right photo below). Your goal is to place the laser pointer’s lens directly on top of your cell phone’s lens.

     

  5. When the putty-wrapped lens touches your cell phone’s lens, you’ll see a reddish rectangle on your screen. This red color is from the blood in your fingertip! If the laser-pointer lens is off-center, the redness won’t be uniform. Instead, there will be a lighter section somewhere on the screen, as shown in the left photo below. Adjust the position of the laser-pointer lens with your fingertip until the red color is uniform across the screen, as in the right photo below. If it's hard to see a color difference, try switching to video mode with the flash on if this setting is available your camera.

     


To Do and Notice

Your Miniscope is ready; now find an interesting object to photograph!

Put your cell phone in camera/photo mode and bring it very close to an object you want to photograph (click to enlarge the photo below). If you’re unsure where to start, try fabrics (denim, cotton shirts, synthetic fibers), flowers, insects, electronic screens, and kitchen spices (salt, pepper, sugar, dried herbs). Adjust your distance until the object is in focus, and then take your photo.

Most microscopes have built-in lights to illuminate your view. If your photos aren't bright enough, ask a partner to shine a light on an object you’re photographing. You can also shoot illuminated videos by turning on your camera’s flash.


What's Going On?

As you can see, adding a laser-pointer lens dramatically increases the magnification capabilities of a cell-phone camera lens.

Although the exact details vary, most cell-phone cameras share attributes with a familiar vision system: an eye! Your eye contains a lens, and a light-sensitive surface (the retina) records an image of what you see.

In a camera, the light-sensitive surface is an electronic screen called a detector. Adding another lens to the cell phone (here, the small but powerful convex lens found in a laser pointer) magnifies everything that’s close to the phone’s camera, similar to the way a magnifying glass works when you look through it. It’s this magnification that makes your Cell Phone Miniscope so mighty.


Going Further

To explore the optics of your Cell Phone Miniscope, try reversing the orientation of the laser-pointer lens by flipping it over, so the side that was against the phone is now facing outward. Take another photo of something you photographed earlier. Did flipping the lens change the magnification and/or quality of the photo? Try putting the laser-pointer lens onto the camera lens on the screen side of your cell phone. How do the images compare?

For another optics experiment, try adjusting the zoom on your cell phone’s camera. Does changing the zoom change the magnification and/or the quality of the photo? You can also experiment by switching to video mode. Does this affect the magnification or quality of the images?

To measure your Cell Phone Miniscope’s field of view, zoom out as wide as you can and focus your camera on a metric ruler. How many millimeters fit across the screen? This measurement is the diameter of your field of view. Zoom in halfway. How many millimeters fit across the screen now? Finally, zoom in all the way, and determine the width of your field of view at this setting.

When you know the fields of view for your Cell Phone Miniscope, you can estimate the sizes of the things you see. For example, if your whole screen’s field of view is 4 mm wide, and 8 salt crystals fit across the screen, then the size of a salt crystal can be found by dividing 4 mm by 8 salt crystals, for an estimated size of 0.5 mm/salt crystal (see photo below).

For an engineering challenge, try designing and building a light box to use as a platform for viewing slides with a light source shining from below, similar to the setup of a typical compound light microscope. Some additional supplies that may be helpful include a push-button night light or small flashlight, popsicle sticks, straws, a take-out container with a clear lid, paper, tape, and other materials.

You can also challenge your estimation skills using data gathered from your Cell Phone Miniscope. For example, how many sugar granules cover a piece of sugar-coated candy?


Teaching Tips

Cell-phone use may be restricted in some school settings. While we believe that use of a cell phone in this Snack is appropriate—especially in classrooms with limited access to microscopes—we encourage teachers to work within their school’s expectations.



Related Snacks

Science activity that demonstrates magnification by a pinhole
Pinhole Magnifier

Who needs expensive optical equipment to see better?

Science activity that demonstrates human visual perception of images on a smartphone
Pixels, Pictures, Phones

Take a (super) close look at your smartphone. You may be surprised by what you see.

Science activity used to determine the field diameter of a compound microscope
What's the Size of What You See?

Determine the field diameter of a compound microscope.



Creative Commons License



This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

Attribution: Exploratorium Teacher Institute

  • Education
    • Teacher Institute
    • Tools for Teaching and Learning
      • Science Snacks
        • Browse by Subject
        • Special Collections
        • Science Snacks A-Z
        • NGSS Planning Tools
        • Frequently Asked Questions



Connect with us!



  •   Sign up for our educator newsletter

  •   Follow #ExploEDU

  •   Teacher Institute YouTube

  •   Teacher Institute Facebook

  •  teacherinstitute @exploratorium.edu

Exploratorium
Visit
Join
Give

Pier 15
(Embarcadero at Green Street)
San Francisco, CA 94111
415.528.4444

Contact Us

  • Plan Your Visit
  • Calendar
  • Buy Tickets
  • Getting Here
  • Store
  • Event Rentals
  • About Us
  • Become a Member
  • Donate
  • Jobs
  • Volunteer
  • Press Office
  • Land Acknowledgment

Get at-home activities and learning tools delivered straight to your inbox

The Exploratorium is a 501(c)(3) nonprofit organization. Our tax ID #: 94-1696494
© 2023 Exploratorium | Terms of Service | Privacy Policy | Your California Privacy Rights |