6,713 免费图片适用于光学

晚上黑暗的技术外层空间电子学天文学黑与白大学天性质

Orbital Antares Rocket at the Launch Pad

Glasses White

Abstract Flowing

Smoke

Flower of Life

School Bus

孩子们载具

Capricorn

medical spectacles

医疗药物机器人

1 Lisb

2 Lisb

Nature Sky

Time-lapse photograph of the Cosmic Infrared Background Experiment (CIBER) rocket launch, taken from NASA's Wallops Flight Facility in Virginia in 2013. The image is from the last of four launches.

外层空间星系

SDO's ultra-high definition view of 2012 Venus transit across the face of the sun. June 5th, 2012.

天文学太阳

Night falls for the Expedition 46 crew of the International Space Station.

外层空间星系

medical spectacles

医疗药物机器人

5 Lisb

Notebook and Highlighters

马克笔筆記本

3 Lisb

9 Lisb

Nature Sky

laser scientific optical system

Space Rocket

Oak Leaf

A rock fishing scene at sunset

laser scientific optical system

star background,

外层空间背景

Prism Splitting Light Rays

Camera Lens

Flying Butterfly

Pluto

冥王星行星

Black hole

multicolor fiber optics

Computer mouse with cord

Apple Under Desk Lamp Light

Satellite View of the Northern Territory of Australia

澳大利亚景观

SECU Daily planet, North Carolina Museum of Natural Sciences

Pair of binoculars

工具类符号

Old book

Black Crt Tv Showing Gray Screen

Moonandstar

外层空间星系

Starburst Tile

马赛克首饰

$Diffraction$

Abstract Light

7 Lisb

Man Drinking

Dark Room

电子计算机技术

Full views of Mir Space Station after undocking during flyaround.

外层空间载具

Abstract Bright

Manila, Students, Conference

Leaves

6 Lisb

Exhibit in the National Museum of Nature and Science, Tokyo

PSM V21 D047 Left and right projection of a cone

PSM V28 D189 Lense of the eye interpreting two simultaneous light sources

PSM V28 D192 Focal distance of a lens from the eye

PSM V28 D187 Circular wave changes when bouncing off the wall of an elliptical bowl

PSM V04 D687 Inverted image of landscape

PSM V11 D679 Light experiment of straight line movement

PSM V04 D686 Image formed by hole in a card

PSM V04 D685 Rectilinear propagation of light

PSM V07 D033 Intensities of the forces of the spectrum

multicolor fiber optics

All Seeing Eye

金字塔三角形

PSM V04 D689 Images of sun formed by foliage

PSM V28 D190 Light wave variation of same object seen through different hole sizes

PSM V28 D191 Light wave divergence traveling through different focal points

PSM V04 D690 Formation of a shadow

PSM V28 D195 Andromeda galaxy seen through various apertures and telescopes

PSM V04 D688 Image of sun upon the floor

PSM V28 D197 Two of the most favoured telescope glasses

PSM V28 D188 Light wave change when traveling through a convex lens

Thesaurus opticus Titelblatt

Red Sign Walking

Stratospheric Observatory for Infrared Astronomy takes off

天文学载具

Arched tunnel in rocket assembly hangar

建筑物科学

Men Nasa

外层空间星系

Telescope on a tripod

天文学望远镜

Mont saintmichel, France, Optics

Tourist Coin

School boy

孩子们学校

Camera Lens

Binoculars

工具类符号

Big Rocks geology rocks

地质学岩石

Scorpio

天蝎座黃道帶

Space Spaceship

Assembly of rocket core at aerospace factory

建筑物技术

Stars Galaxy

Brightness elementary school light

Green Telescope

天文学绿色

Sunflower petals isolated on white background

Sunflower petals

Sphärische Linse plankonvex

Geometry, Illusion, Sunset

Candlelight county students

Acid deoxyribonucleic acid electrophoresis

$Optics optometria refraction$

Sphärische Linse bikonvex

Test myopia lyrics

Trees, School, Girl

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