Wavelength Scan: Instrument Tab
F.1.1 Wavelength Scan: Instrument Tab
Parameter Name
Setting Range
Data mode
%T, Abs, E(S), E(R), %R (U-1900: %T, Abs, E(S) and E(R) alone) (U-5100: %T and Abs alone)
Start wavelength
Model Input range
U-1900/2900/2910/
191.00 to 1100.00 nm
3900/3900H/5100 U-4100/UH4150
176.00 to 3300.00 nm
End wavelength
Model Input range
U-1900/2900/2910/
190.00 to 1099.00 nm
3900/3900H/5100 U-4100/UH4150
175.00 to 3299.00 nm
Scan speed (nm/min)
Model U-1900/ U-3900/
U-4100/ U-5100
High Resolution
On, Off
(U-3900/3900H/ 4100)
Response
Fast, Medium, Slow
(U-1900/2900/ 2910/5100)
Parameter Setting Range Name
Baseline correction
Model U-1900 U-2900/
Input range
User
System System User 1
User 1 User 2
User 2 None
User 3 User 4 None
[System baseline measurement conditions] Data mode
: Abs Start wavelength
: 10 nm End wavelength
: 190 nm Scan speed
: 300 nm/min High Resolution
: Off Delay
: 0s Lamp change mode
: Auto Lamp change wavelength : 340 nm Slit width
: 2 nm PMT mode
: Auto Sampling interval
: Auto Delay
0 to 3600 s Cycle
175.0 to 99.0 min Time
Settable when “2” or more is specified for Replicates.
Parameter Name
Setting Range
Auto Zero before ON, OFF each run
When turned ON (checked), the auto zero wavelength is settable.
Model Input range
U-1900/2900/2910/
190.00 to 1100.00 nm
3900/3900H/5100 U-4100/UH4150
175.00 to 3300.00 nm Data Int. (with
Normal, Fine U-5100)
The data interval can be changed. The actual data interval differs depending on the scan speed and measuring wavelength range. For details, refer to APPENDIX G.1.
UV Scan speed ON, OFF change function
When turned ON (checked), the speed change (with U-3900/
wavelength and scan speed are settable.
3900H)
Speed change Wavelength:
Input range
191.00 to 370.00 nm
Scan speed (nm/min): 2400 1800 1200
Lamp change Auto, D2 only, WI only mode (with other than U-5100)
Lamp change 325.00 to 370.00 nm wavelength (with other than U-5100)
WI Lamp (with On, Off other than U-5100)
D2 Lamp (with On, Off other than U-5100)
Parameter Name Setting Range
Slit width (nm)
Model U-3900/3900H
Input range
U-1900 : Fixed at 4 nm
U-2900/2910 : Fixed at 1.5 nm U-5100
: Fixed at 5 nm U-4100/UH4150 : Select a slit width in the
ultraviolet/visible region. It is recommended to fix the slit width for ordinary measurement.
Auto : The slit width is automatically controlled according to the optical energy level under a specified photomultiplier voltage. Concretely, the slit width is widened at a low optical energy level and narrowed at a high optical energy level. In other words, this is a function depending mainly on the S/N ratio (signal-to-noise ratio). In this mode, the slit width automatically changes in a range of about 0.01 to 14 nm. This mode cannot be set simultaneously with PMT mode “Auto”.
Fixed : The slit width is selectable in a range of 0.1 to 8.0 nm in 0.01 (0.02) nm steps. (The parenthesized step corresponds to slit width 2.4 nm or wider.)
Parameter Name Setting Range
PMT mode (with Auto, Fixed U-3900/3900H)
When “Fixed” is selected, the photomultiplier voltage is settable.
PMT mode (with Auto, Fixed U-4100/UH4150)
When “Fixed” is selected, the photomultiplier voltage is settable.
Fixed : Used for measurement in the energy mode. The voltage to be applied to the photomultiplier will be fixed at an entered value. Input range: 0 to 1000 V
Auto 1 : Used for ordinary measurement. Auto 2 : The photomultiplier voltage at each
wavelength is stored at user baseline measurement and a sample is measured at the stored photomultiplier voltages. This mode is effectively usable at a slow scan.
PMT voltage (with
0 to 1000 V
U-3900/3900H/ 4100/UH4150)
Sampling interval (nm)
Model U-3900/3900H U-4100/UH4150
Input range
With the U-1900/2900/2910, the sampling interval is automatically set according to the wavelength interval and scan speed. For details, refer to APPENDIX G.1.
Replicates
1 to 99
Path correct ON, OFF When turned ON (checked), cell length correction is
effective. Path Length
0.1 to 100.0 mm
Parameter Name Setting Range
Attenuation (with The beam attenuator is inserted on the reference U-4100/UH4150)
side. Set the attenuation ratio of the attenuator. This setting is usable for a sample whose absorbance and transmittance/reflectance are 4 Abs or more and 0.1%T or less, respectively. For usage, select the Attenuation command from the Spectrophotometer menu after baseline measurement. Then, carry out sample measurement.
None 1/10 1/100
Detector change A function for automatically correcting the difference correct (with
in photometric value between the detector U-4100/UH4150)
changeover points in the near infrared and visible regions.
On Off
Detector change Set up a wavelength for changeover between the wavelength (with
detectors for the ultraviolet/visible and near infrared U-4100/UH4150)
regions. Input range: 700.0 to 900.0 nm
Scan speed (with Set up a scan speed in the near infrared region. U-4100/UH4150)
0.75 nm/min
Parameter Name
Setting Range
Slit width (with
Set up a slit width in the near infrared region.
U-4100/UH4150)
Fixed : Input range: 0.1 to 20.0 nm, in 0.1 nm
steps Auto : The slit width is automatically controlled
according to the optical energy level. This function is intended to keep the S/N ratio (signal-to-noise ratio) constant in the measuring wavelength range as far as possible. In this mode, the slit width automatically changes in a range of about
0.1 to 36 nm. This mode cannot be set simultaneously with Light control mode “Auto”.
PbS Gain (with
Specify a sensitivity level of the detector for the near
U-4100/UH4150)
infrared region. The PbS sensitivity is settable at four levels. Level 1 is used as a reference. Levels 2, 3 and 4 are 2, 4 and 8 times as high as level 1, i.e., the sensitivity rises in the order of 1, 2, 4 and 8 (times). For high resolution measurement in the near infrared region, use a higher sensitivity (PbS sensitivity level 3 or 4). However, use of a high sensitivity inevitably entails an increase in noise level. Therefore, PbS sensitivity level 2 is generally recommended. Use Pbs sensitivity level 1 for measuring quite a flat spectrum with no large absorbance change or checking spectral features alone with minimum noise.
Light control mode
A mode for controlling the light quantity in the near
(with U-4100/
infrared region.
UH4150)
Fixed : Used for ordinary measurement. Auto : Used when measurement cannot be
performed with the slit width fixed because the light quantity in the near infrared region is excessive.