Technical note

Optics modules

Contents

P. 01

Overview

P. 02

Features

P. 02

Hamamatsu technologies

3-1

COB (chip on board)

3-2

Optical technology

P. 03

Structure

4-1

Beam splitters

4-2

Band-pass filters

4-3

Si photodiodes

4-4

Signal processing circuits

P. 03

Characteristics

5-1

Detection center wavelength

5-2

Full width at half maximum

5-3

Stray light

5-4

Sensitivity

P. 05

How to use

P. 06

Applications

7-1

Blood analysis device

7-2

PCR inspection equipment

Overview

The optics module is an optical module for absorbance

measurement, with a structure including Si photodiodes,

optical filters, and I/V conversion circuits. Si photodiodes

of multiple channels do detection by dispersing incident

light such as light transmitted through a solution. The

generated photocurrent is subjected to photoelectric

conversion, and signals of various wavelengths are

output as analog voltage simultaneously.

The optics module is a non-dispersive spectroscopic

module, with a spectroscopic system that uses optical

filters (beam splitters, band-pass filters). The dispersive

mini-spectrometer disperses light with a grating, providing

an optical spectrum with continuous wavelengths. In

contrast, the optics module detects light of up to 10

different discontinuous wavelengths. Optics modules

are suitable for applications including blood analysis

and water quality analysis, where detection wavelengths

are specified, because S/N at the detection

wavelengths

and the blocking (light-shielding) characteristics of non-

detection wavelengths are better than those of the

dispersive type.

[Figure 1-1] Optics module C13398 series

Features

Simultaneous detection of up to 10 wavelengths (C13398 series)

The optics module can simultaneously detect up to

10 wavelengths of light. Combining the C13398 series

with the evaluation circuit C13390 (sold separately)

makes it possible to convert analog signals to digital

signals and send the signals of 10 wavelengths to a PC

connected by USB simultaneously.

[Table 2-1]

Detection center wavelength (C13398 series)

ch C13398-01 C13398-02 Unit

1 340 340

2 405 380

3 450 405

4 510 492

5 546 510

6 570 546

7 600 578

8 630 620

9 660 690

10 700 White light

[Figure 2-1] Evaluation circuit C13390

Excellent light-shielding characteristics

Using Hamamatsu mounting technology, assembly

technology, and optical technology, we can reduce

optical and electrical crosstalk between channels

and achieve superior light-shielding characteristics

for light with non-detection wavelengths. Doing

so enables wide dynamic range and high accuracy

measurement.

Flexible customization

We offer custom support for specifications such as

detection wavelength and the number of channels

[Table 2-2].

[Table 2-2] Customization

Description Difficulty

Change detection wavelength Easy

Change half width

Easy to normal

Decreased number of detection channels Easy

Increased number of detection channels

(up to 13 channels)

Normal

Increased number of detection channels

(14 channels or more)

Hard

Changes to incident beam system

(e.g., change to fiber input type)

Easy

Change circuit gain Easy

Change case Normal

More compact size

Normal to hard

Adding functions to the circuit

Normal to hard

Change optical system Hard

Hamamatsu technologies

COB (chip on board)

3 - 1

The optics module uses COB technology to mount

photodiodes directly to the circuit board. The COB

technology enables the photodiodes to be mounted

with high accuracy and the photodiode packages to be

made compact.

Optical technology

3 - 2

We have done optical design using optical simulation,

realizing a highly reliable optical system that reflects

our simulation results.