医療用イメージング用レンズ：マウントの選定、センサーとの適合、およびマシンビジョン検査用光学系
Choosing a lens for a medical imaging camera or a medical device inspection line comes down to sensor geometry, mount class, and distortion tolerance. Inspection stations add a fourth factor: depth of field. This guide covers both threads with the same underlying optics.
Medical imaging lens selection is a system-design problem, not a lens-catalog lookup. The right lens matches the sensor's image circle and CRA, fits the device package, and keeps distortion inside the software pipeline's tolerance. Use M8/M7 for extreme miniaturization, M12 for compact embedded modules (most models up to roughly 1/1.8 inch, select models to 1/1.7"–1/1.6"), and C-mount for larger sensors or when an adjustable iris is needed for depth of field.
What Makes a Lens Suitable for a Medical Imaging Camera?
A suitable lens matches the sensor's image circle and chief ray angle (CRA), the angle at which light from the lens meets the sensor at the frame edge. It also holds geometry within the software pipeline's distortion tolerance, responds correctly to the illumination wavelength, and fits the device package. Commonlands specifies image circle and distortion for every lens in this guide, so these geometry checks can start from published numbers.
These are stock catalog optics. They fit device development, prototyping, and non-diagnostic lab or inspection stations. Patient-contact optics, assemblies that face repeated sterilization, and lenses that carry regulatory qualification inside a finished device run through a custom development path instead.
A capsule endoscope module and a bench inspection instrument are different optical problems. The endoscope module may be constrained to a 5mm–8mm diameter with no room for lens mechanics, which pushes the design toward M8 or M7 optics built around the smallest possible form factor. For teams building high-stakes imaging workflows, the optical specification is a software reliability constraint, not just an image-quality preference.
Should I Use M8, M12, or C-mount for Medical Imaging?
Use M8 or M7 for development work at extreme miniaturization, the scale of capsule and catheter-tip modules, where diameter dominates every other constraint. Use M12 for compact embedded modules, where size, cost, and optical performance balance well. Most models cover sensors up to about 1/1.8 inch, with select models reaching 1/1.7"–1/1.6". Use C-mount when the sensor is larger or the instrument housing has the depth to accommodate the larger lens body. It is also the right choice when the system needs an adjustable iris for depth-of-field control.
| マウント | 代表的な像円 | パッケージ | アイリス | 一般的なセンサーの取り付け方法 | 医療画像の文脈 |
|---|---|---|---|---|---|
| M8 / M7 | 最大で約5mm～6mm | 極小サイズ | 修正済み | 1/4インチ以下 | Development optics at endoscope-tip, capsule, and catheter scale |
| M12 | 最大約9mm～10mm | コンパクトな組み込み型 | 修正済み | 最大 1/1.8 インチ（1/1.7 インチ～1/1.6 インチから選択） | Compact embedded modules in device development, lab and inspection cameras |
| Cマウント | 最大約20mm～22mm | 装置／実験台 | 調整可能 | 最大1.1インチ以上 | Bench lab instruments, larger-sensor imaging heads, microscopy ports |
The Commonlands M12 catalog spans 0.8mm to 100mm focal lengths. The picks below map the medical use cases to specific SKUs.
C-mount and M12 are different optical systems, not two sizes of the same design. Commonlands C-mount lenses use cam-driven focus; the focus mechanism and its near-limit behavior are product-specific, so check the product page. The mount standard itself dictates no focus mechanism; other C-mount lenses use unit or front-cell focus or ship fixed-focus.
M12 is a rigid optical assembly: focus is set by threading the entire lens in or out of the holder, with no internal group movement. Neither is a lesser version of the other. They trade in-barrel focus and iris control against size, weight, and simplicity.
How Do Focal Length, Sensor Size, and Image Circle Interact?
センサーとレンズの選定は相互に密接に関連しています。一方を先に決定し、その後で他方を適合させようとすると、設計サイクルの後半になって互換性の問題が発生することになります。イメージサークルはセンサーの対角線長を上回っている必要があり、焦点距離は作動距離と必要な画角を総合的に考慮して決定しなければなりません。
Nominal sensor format numbers (1/2", 1/1.7", 1/1.8") do not directly map to active-area dimensions. The active area has to be read from the sensor datasheet.
Do Medical Imaging Lenses Need Low Distortion, and Why Does CRA Matter?
Distortion and chief ray angle both have outsized effects on software pipelines relative to how visible they are on raw image inspection. Distortion is a direct source of measurement error in any pipeline that assumes rectilinear geometry. CRA mismatch causes corner shading and color non-uniformity that flat-field calibration cannot fully correct. Both should be specified explicitly before lens selection, not discovered during validation. Commonlands publishes each lens's rectilinear distortion figure, so the pipeline tolerance can be checked against a real number before selection.
Distortion places pixels at positions that do not match the correct rectilinear projection of the scene. Barrel distortion pulls edge pixels toward the center; pincushion distortion pushes them outward. By the usual sign convention, negative distortion is barrel and positive is pincushion.
Chief ray angle is the angle at which the principal ray from the lens meets the sensor plane at a given image height. Small-pixel CMOS sensors shift each on-chip microlens laterally toward the array center, by an amount that grows with image height, so a chief ray arriving tilted still lands on the photodiode.
When the lens CRA departs from the profile the sensor was built for, the microlenses steer part of the cone away from the photodiode. The result is corner shading on monochrome sensors and color non-uniformity on color sensors, because the color filter channels are affected unevenly. Acceptance is not a single degree figure: it depends on the full cone (f-number), wavelength, pixel stack, and how much shading or MTF loss the pipeline tolerates.
When Are IR-Cut or NIR Filters Needed in Medical Imaging?
IR-cut filters are needed whenever the sensor responds beyond visible light and enough near-infrared energy reaches the scene to bias color. Halogen, incandescent, and ambient daylight carry significant NIR. Dedicated NIR LEDs do by design, but standard white LEDs emit little energy beyond 700nm. The IR-cut question is driven by the sensor's NIR response plus whatever NIR actually reaches the scene, not by an assumption that the illumination source itself is NIR-rich. Browse Commonlands optical filters for compatible options.
What Machine Vision Lens Should I Use for Medical Device Inspection?
レンズカタログからではなく、検査タスクから検討を始めましょう。組立検証やUDI読み取りでは、歪みが少ないことが重要であり、そうすることで視野全体にわたって形状やコード記号を正しく読み取ることができます。パッケージングおよびシール検査では、実際のパッケージの高さばらつきにより被写界深度の確保が課題となるため、アイリス調整機能付きのCマウントレンズが適しています。電子医療機器内部のPCB検査では、これら両方の課題が共通して生じます。寸法計測のみがテレセントリック光学系を採用する正当な理由となるケースであり、その他のほとんどのタスクでは必要ありません。
| 点検作業 | 主要な光学要件 | デフォルトのフォームファクター | アイリス制御は役に立つ？ |
|---|---|---|---|
| 組立検査（注射器、針、点滴用部品） | 歪みが少なく、特徴点配置の確認に十分な解像度 | CマウントまたはM12 | 場合によります。組み立て時の高さのばらつきによります。 |
| 包装・シール検査 | パッケージの高さによる被写界深度の変化、シール境界におけるコントラスト | Cマウント | はい。キャビティの段差やビードシールに対応した調整可能なアイリスが付いています。 |
| UDI／バーコード／ラベル読み取り | シンボルの形状を保持するための低歪み、微細なマークに対応できる十分な解像度 | M12またはCマウント | それほど深刻ではない。傷は通常、平らな面に生じている。 |
| PCB検査（電子医療機器） | フィデューシャルおよびジオメトリタスクにおける歪み、実装済み基板の高さを超える自由度（DOF） | Cマウント | はい。コンポーネントの高さのばらつきは、アイリス制御によって改善されます。 |
| インプラント表面／寸法計測 | 倍率の安定性、低歪み | テレセントリック（外部ベンダー製）または低歪みCマウント | Model-specific; many commercial telecentric lenses do offer an adjustable iris |
Commonlands does not currently sell telecentric lenses. Specialist optics vendors supply them for the narrow set of tasks that genuinely require magnification constancy.
Top Lenses for Medical Imaging and Device Inspection by Use Case
Match the lens to the job first, then the sensor. Miniature module development starts with the M8/M7 series, and compact embedded modules run on M12. Bench instruments or inspection stations that need an adjustable iris move to C-mount. The table maps Commonlands stock lenses to the use case each one fits, using the specs published on each product page. All ship same-day on orders placed before 12 PM PT.
| ユースケース | レンズ | マウント | EFL | この選手を選んだ理由 |
|---|---|---|---|---|
| Miniature module development (endoscope and catheter scale) | M8／M7シリーズ | M8 / M7 | 短期・固定 | Smallest diameter when the package dominates every other constraint. Fixed aperture and limited image circle. A development and prototyping starting point: tip geometry, biocompatibility, and sterilization push a finished device toward custom optics. |
| Compact embedded module (device development camera) | CIL085 | M12 | 8.2mm | 1/1.8" coverage, 57° FOV, -0.9% distortion, 8.9mm image circle. Mid-FOV workhorse for an embedded module. On a 1/1.7" sensor (~9.4mm diagonal), the corners fall outside the rated circle, so verify corner performance or step up to a larger-circle lens. |
| Bench instrument optics (longer working distance) | CIL121 | M12 | 21.8mm | 500mmの作動距離に合わせて補正された有限共役M12レンズであるため、長共役レンズでは解像度が低下する距離でも、隅の解像度が維持される。 |
| 機器／カート搭載型イメージング（コンパクトCマウント） | CIL561 | Cマウント | 6mm | 1/1.7インチ、画角76°、歪率-2%、ベンチヘッド搭載のF/2.4調整可能アイリスによる被写界深度制御。 |
| 機器／カートを用いたイメージング（高解像度） | CIL544 | Cマウント | 25mm | 1.1インチ、20MPクラスの撮影範囲、17.6mmのイメージサークル、大型センサー搭載イメージングヘッド向けの130mm～無限遠のWD。 |
| 機器の検査／UDIの読み取り | CIL052 | M12 | 5.2mm | -0.1%の歪み率により、F/3.4で最大1/1.8"の範囲において、データマトリックスおよびバーコードの形状をフィールド全体で維持します。 |
| Washdown-line inspection (sealed) | CIL059 | M12 | 5.9mm | IP67-sealed variant: dust-tight and tested to 1 meter immersion for 30 minutes under IEC 60529, for the tested variant in its mounted configuration. That rating covers water and dust only. It says nothing about disinfectant compatibility, repeated wiping, sterilization, biocompatibility, or the assembled device. F/1.7 to F/5.6 selectable at procurement. About -4% distortion suits contrast-based checks, not geometry-critical reads. |
| パッケージ／PCB検査（被写界深度） | CIL522 | Cマウント | 12mm | F/1.4～F/16の可変絞り、0.4%の歪曲、11.4mmのイメージサークル。パッケージの高さの違いによる被写界深度を確保するため、絞りを絞る。 |
These stock lenses fit prototyping, bench and lab instruments, and inline inspection stations, where the optic sits behind a window or housing and never touches the patient. Patient-contact optics, lenses that have to survive repeated sterilization cycles (autoclave, EtO, gamma), and any lens that must carry regulatory qualification inside a finished device all need a custom development path. A catalog part will not cover them. If that is your case, send the requirement to engineering for a custom quote.
よくある質問
医療用画像撮影レンズとは何ですか？
A medical imaging lens is an optical assembly selected to produce repeatable, geometrically accurate images for medical device development and for non-diagnostic lab and inspection work. It is chosen for sensor compatibility (image circle, CRA), distortion performance for the software pipeline, wavelength response for the illumination source, mount class for the device package, and reliability in the operating environment.
Catalog options span miniature M8 lenses through larger C-mount lenses for bench instruments. Patient-contact optics, assemblies that face repeated sterilization, and any lens carrying regulatory qualification inside a finished device need a custom development path instead.
医療用カメラ用のレンズはどのように選べばよいですか？
レンズを評価する前に、以下の6つのパラメータを定義しておく必要があります。必要な視野角と作動距離、センサーのフォーマットとピクセルピッチ、マウントクラスを決定するパッケージの制約、ソフトウェアパイプラインが要求する歪みの許容範囲、センサーによって制限されるCRA予算、および照明が使用する波長スタックです。センサーとレンズは同時に選定すべきです。先にレンズを選んでからセンサーを合わせるという方法では、再設計が必要になる傾向があります。
医療用画像撮影には、M8、M12、それともCマウントのどれを使うべきでしょうか？
Use M8 or M7 for development work at extreme miniaturization, the scale of capsule and catheter-tip modules. Use M12 for compact embedded modules. Most models cover sensors up to about 1/1.8 inch, with select models reaching 1/1.7 inch to 1/1.6 inch. Use C-mount when the sensor is larger or the instrument housing has room for the larger lens body. It is also the right choice when the system needs an adjustable iris for depth-of-field control.
医療用画像診断において、IRカットフィルターやその他の光学フィルターはどのような場合に必要となるのでしょうか？
IR-cut filters are needed whenever the sensor responds beyond visible light and enough near-infrared energy reaches the scene to bias color. Halogen, incandescent, and ambient daylight all carry significant NIR. Dedicated NIR LEDs carry it by design too, though standard white LEDs emit little energy beyond 700nm. The IR-cut question is driven by the sensor's NIR response plus whatever NIR actually reaches the scene. NIR-pass or narrow-band filters are needed instead when the application specifically images in the near-infrared or fluorescence-adjacent bands. Browse optical filters for compatible options.
医療機器の検査には、どのようなマシンビジョン用レンズを使用すべきでしょうか？
Start with the inspection task, not the lens catalog. Assembly verification and UDI reading benefit from low distortion. Packaging and seal inspection create depth-of-field pressure from package height variation, favoring an adjustable-iris C-mount lens. PCB inspection inside electronic medical devices shares both requirements. Dimensional metrology is the one case where telecentric optics may be justified, since most other tasks do not need them. Commonlands options include the CIL052 (5.2mm M12, -0.1% distortion), CIL059 (5.9mm M12, IP67 variant), CIL522 (12mm C-mount, adjustable iris), and CIL544 (25mm C-mount, 20MP+ coverage).
チームは、レンズを本番環境に導入する前に、どのような点を確認すべきでしょうか？
実際の作動距離において、センサー全域にわたる画質（解像度、歪み、シャドーイング、色精度）を検証するほか、特定のセンサーとのCRA互換性、動作温度範囲全体にわたる焦点の安定性、デバイスが臨床用表面に接触した場合の耐汚染性、現場環境下での機械的信頼性、およびレンズとセンサーの位置合わせの製造可能性を検証する。すべての検証において、代替品ではなく実際のセンサーおよび光源を使用すること。
Have a Sensor and Working Distance in Hand?
Commonlands manufactures M12 and C-mount lenses for medical imaging cameras and medical device inspection stations, with published distortion specs and MTF test data available for select lenses. ISO 9001:2015 certified. Samples ship same-day on orders placed before 12 PM PT.